Join Our Ford Truck Forum Today

Document your Ford truck project here and inspire others! Login/Register to view the site with fewer ads.

1992 4.9L auto F-150 Starts Stalls, runs rough rev'd and kept in gear to keep going

Kaajot

Micro Machine Manager
Hello-

I've been working on my red F-150 for two years now, and we're almost to the point where I could show new pictures of the truck with some major mods. However, I'm back with a new stumper.

The truck will start (strong battery and connection) and then stall. There is black smoke out the pipe if I do this several times.

If I crank it with my foot on the break and keep the rpms up (likely doing damage to the transmission/flex plate, etc), I can switch the automatic transmission into drive or reverse and then take off, but as soon as I get to a stopping point or low mph (below 15-20 mph) it will die. This wouldn't be as big a deal with a manual transmission, but driving an auto with two feet is unnerving.

Finally, the last time I pulled this "hack" to get from point A to B I stopped several times in town and by the time I was headed home it was running rough and felt like it was skipping or misfiring.

A little history since a new transmission/engine job in 2015.

- Has f250 back suspension now.
- Has spacers on all wheels, next step up springs, heavy duty shock absorbers at all 4 points, and 275/75 wheels on the 15 rims.
- New Gear Box, tie rods thanks to twisting it in a ravine.
- New throttle body spacer and high performance K&N air filter
- Has new sparks as of 2015, new cap/rotor, and all new fuel injectors from Summit Racing with a slightly higher flow.
- Replaced IAC, tab, tad & egr solenoid sensors, MAP sensor, oil pressure sensor, new water pump, new starter.
- Other stuff is electronics like new fog lights, amp, stereo system, etc.

Since the engine/tranny swap there has been a slight manifold leak because the engine guy that was helping me sandwiched two gaskets together to try to repair it rather than take it off, smooth it out, and use the second gasket.

The tranny is also an AOD 4.9L and I have an E40D wiring system/engine, so I'm going to put a new E40D in soon. Currently the only EOD/EOR diagnostic code is low rpms to switch caused by the incorrect AOD. This was also installed by a shop for over $1K -- if I'd known better I would have never authorized him to rush the job and put an AOD into my E40D. My gas mileage has gone down over time.

Speaking of gas mileage, I used to get 19-22 mpg on the highway and now I"m in the 8-15 mpg, closer to 10 mpg since the engine has started cutting off.

Other symptoms when the engine dies is a noticeable drop from 12-14v to 10-11v before it dies. I thought the battery or alternator might be bad, but they work fine with the rpms engaged and stay charged. I only drained the battery trying well over two dozen times to get this thing to start the first time I experienced the cut-off symptoms after every start. The engine would die 2-8 seconds after it'd turn over and the drop in voltage was always observable as it began to die. This is more indicative of the alternator working properly and dropping in voltage generation as the engine rpms would drop.


Solutions:

SO far, I've been told to trouble-shoot the following: Check TPS, MAP, EGR Valve, pressure test/check the system for cuts/damage in the airflow tubes, check/clean the IAC, check the ignition module and engine modules, check the ECM for the computer's capacitor's for damage and fix them (radioshack soddering job) or buy a new ECM ($100-$200), and if all that fails, I've been told the distributor and ignition coils are the overlooked culprits.

I've read symptoms diagnostics via google of a bad distributor and it matches my symptoms, but it's one of those wiki doctor type answer and I wanted some feedback from this community.

Any opinions or alternative suggestions? Should I latch onto a new distributor? That's one part I've not changed in the new engine swap.

Appreciate any and all help, need to get this truck running! smiliegitrdone

-KJ
 

Sparky83

Virginia Chapter member
5,566
219
Norlina NC
in some ways theres still too many unknowns..


  1. when the swaps were done did they ever retune the computer to correctly fuel and run this engine??
  2. whats the fuel pressure reading at?? (black smokes an indicator its running rich. if your getting large cloud of it then its really over fueling)
  3. have you actually checked to insure the ignition components are actually firing correctly?? (just because theyre new doesnt mean they actually work correctly.. ive literally had new parts outta the box that were bad)

the voltage drop can be a cause of the stall but can also be a symptom coming from the fact the engines stalling.. Slower the engine turns the less ability the alt has to generate the proper amps/volts.. 11-12v is norm for engine off key on... 13-14v is the norm for Key On Engine Running..

not sure on the 92.. but since you mentioned having a distributor id check to make sure the timings set correctly...too far advanced or retarded will cause the same running issues... if it hasnt been changed it could be the issue.. same if the plugs wires are not on correctly..
 

Kaajot

Micro Machine Manager
Hey Sparky83-

SO no, never retuned the computer after the swap with the AOD, nor after the engine.

We'll be finding out fuel pressure tomorrow at the shop.

Not sure about the ignition firing components? So, the spark plugs initially had been a problem because someone (helpers) dropped one and closed the gap, causing a big misfire. We caught that in July or Aug 15 and fixed it, seemed to "fix" the immediate running rough problem. Haven't checked the spacers since on the spark plugs, so some gap adjustment could help. The Distributor coil was replaced too I believe at this time, but not the distributor itself.

I'm pretty certain the plugs wires, they're on correctly. I must have checked the firing order a million times because help was wanting to wing it, but I showed them the correct firing order from multiple sources and that's what we went with -- it ran for 2 years? Got about 20K miles running in the current configuration.

Timings definitely will be getting looked at. I think the original engine mechanic adjusted those initially 2 years ago because it was getting too much fuel and flooding itself due to the AOD and higher fuel flow/pressure injectors.
 

Kaajot

Micro Machine Manager
Update:

There were two broken wires on the ignition control module. Patched those up, improved a little, still running very rough and cutting out but held up a little longer.

The transmission is shifting rough and gas is in the oil, prompting a new oil change once we get a few more diagnostics out of the way. The E40D transmission is getting pulled out of the donor tomorrow to replaced the AOD that never should have gone into the truck in the first place.

Do not ever go to Big Mike's Garage in Liverpool, NY. He put an AOD transmission into my E40D, charged me $1K for it, and it had the broken bell housing when we went to pull the engine 3 weeks later because it was again, running rough (similar to now but not cutting out). Not only does he not know what he's doing when it comes to older trucks but he's actually quite short (maybe 5'4") and looks a lot like George Castanza from Seinfeld -- the name Big Mike is quite misleading.

Hopefully will hear from the mechanic Monday on some pressure checks both fuel and air.
 

smokey

Hitech hillbilly
Staff member
Sound like you may have a fuel injector sticking open. Causing it to flood. Might want to pull the injectors or at least put noid lights on to check the signal to the injectors.
 

Sparky83

Virginia Chapter member
5,566
219
Norlina NC
when you say you fixed the "dropped" spark plug.. what did you mean by that?? just regapping the plug? or actually replacing it with a whole new one? reason i ask is the internal cores on the plugs are just as fragile as the ceramic outer insulator they can crack internally when dropped causing a short which can cause a misfire...

it definitely sounding like theres a fueling issue in there..
 

Kaajot

Micro Machine Manager
when you say you fixed the "dropped" spark plug.. what did you mean by that?? just regapping the plug? or actually replacing it with a whole new one? reason i ask is the internal cores on the plugs are just as fragile as the ceramic outer insulator they can crack internally when dropped causing a short which can cause a misfire...

it definitely sounding like theres a fueling issue in there..

Oh bother. Ok, looks like I'll get a new set.

Yes, we just regapped it. We don't know who "closed" the gap and how it was done. It could have been dropped or it could have been a careless press against metal before getting it into the hole. Sadly, I'm not sure which one or two were regapped, so maybe we'll be changing the spark plugs tomorrow too. Several helping hands wound up in the original gap error.

We're getting back at it in 6 hours, will update in another post, but appreciate the feedback. Sounds like I'll replace the sparks after only 2 years, which isn't terrible but was hoping to get 1-2 more years at least out of them.
 

Kaajot

Micro Machine Manager
Sound like you may have a fuel injector sticking open. Causing it to flood. Might want to pull the injectors or at least put noid lights on to check the signal to the injectors.

I'll talk to the guys and see if we can pull the injectors out tomorrow and check it out. Thanks for the feedback!

Really hope they're not sticking open. The injectors were all new (the old ones were horrible, looked like they'd never been changed). And they were pretty expensive if I recall from Summit Racing -- about $180-$200 for all of them.
 

Kaajot

Micro Machine Manager
Update:

Ok, so we've done some stuff to the Truck and found some stuff.

1. There were two wires that were clipped on the ignition control module. Those have been mended, although my buddy may pull them apart again and sodder them up instead of using the quick fix metal clip technique.

2. We picked up an E4OD transmission with 170K miles. It's clean, not broken, and we're degreasing it right now overnight. The AOD is out of Red and boy was it messed up. The shifting problem was there because somewhere along the way that transmission lost all its fluid (did not leave a trail, so no idea where or when this happened!) They got maybe 2 quarts out of the AOD when they pulled it out along with a ton of metal shavings and silver filter. It was about to go, so this is good timing. We basically got 20K miles out of the AOD in the truck. I still want to sue the shop that thought it was acceptable to put an AOD in my truck (when I didn't know any better). Again, Avoid Big Mike's Garage in Liverpool, NY at all costs. His Yelp review is not reliable.

2.1 We shot the continuity through the wiring harness for the transmission and all wires are 100% good to go testing at 1.1-1.2 and one hit 1.0, but still pretty good readings. Happy that there are no bad wires in the harness.

3. We're putting a new distributor and distributor coil in the truck tomorrow too. This combo may fix a lot of the misfiring causing the oil to flood with gas.

4. The fuel pumps are good -- I have a dual tank and both tanks act the same way. I don't think the fuel pumps would both go bad at the same time and the selector works fine.

5. I may pull out the ECM tomorrow after I do a lube job while they're working on the engine and inspect it for damage to the capacitors and any other possible corrosion damage to the circuit board. That'll at least tell me if the ECM is good or not and if it is damaged it can be a big reason why the fuel/ignition controls have been less than stellar.

6. Still have to check and clean the TPS, IAC, and EGR Valve. Will do if there's time after the ECM and lube job.

Thanks again for the pointers -- we'll probably change the spark plugs again and check the injectors for any problems there. smiliegitrdone
 

Kaajot

Micro Machine Manager
The Good, The Bad, The Ugly

Update 3.1

The F-150 now has an E40D Transmission in it. It works. It improved the running and idle of the truck, big time, but that also had to do with the idle throttle being off. We adjusted it to the right RPM at idle and a few things happened. 1. The Serpentine Belt stopped squeaking! 2. The "knock" we felt in the engine went away and purred. So that was great. And it was rarely stalling at idle.

Besides that, we put a new distributor coil in but did not get to the distributor itself. The coil was pretty darn old (ie factory original) so we swapped it out since it was an easy $21 part we had. We may still have to try the distributor.

Now, it still stalls on idle because we found something while putting the mounting brackets for the transmission back into the motor -- the EGR Tube was completely disconnected from the catalytic converter/exhaust manifold area because of a righteous rust failure. Yeah, it's clanking around and not secure, causing all kinds of noise and pressure issues.

So, before we do anything else, the EGR Tube is next on the list later this week. The Truck heated up and started failing again (apparently in colder weather you can do without the EGR Tube connected, but when it's 80 degrees+ and you're running hot, it will stall and clunk and the transmission started acting sluggish at that point. When it was cold it was running great.

Also of note -- left side of engine (while in driver seat) has a severe oil leak. It makes the engine smoke. The black smoke out the tail pipe has disappeared, but the smoke under the hood was unsettling. I'm going to get the new manifold/gasket for the side pan on the 4.9L (I have no idea what this part is called atm) and disconnect a few oil lines and get it fixed so the oil slick goes away. The truck also needs the oil change from all the fuel that was dumped previously due to the poor performance (EGR and throttle tuning).

That's where we're at. Really can't give a better bullet point statement of facts until the obvious repairs have been done and then we can see what happens.

Side-note: The current 4.9 300 L6/v6 engine is not the original, but it has been rebuilt and overbored. It has run decently over the last 20K miles and we'll probably keep it in unless the knock doesn't completely disappear. The original engine had a minor head job required and is currently in the shop with most of the parts, being VERY SLOWLY rebuilt by a mechanic friend in his spare time. If we have to, the original engine with 126K miles on it will be finished and swapped if this engine is showing signs of failure after all other fixes have been accomplished.

Also, we have not done anything as far as calibration goes. Any helpful guides on transmission/engine tuning/calibration are welcome. My Haynes guide is missing and mostly trashed last time I did see it, so I've just been referencing online tutorials and fact/data sheets.

So far we're about $450 into the repairs but that was including a new-to-me and correct model transmission. :cooldude:
 

Sparky83

Virginia Chapter member
5,566
219
Norlina NC
sounds like your making progress there... hope it keeps going in the + direction... its always frustraiting when you have a problem and the diagnostics are not helping like they should...
 

Kaajot

Micro Machine Manager
Update 4.0

Great news.

After fixing the wires, replacing the distributor coil, correcting the AOD transmission with a nice 170K E40D transmission (like it should have been the first time), we tried the distributor to stop the stalling.

The new-to-me distributor we borrowed form the same donor that gave the correct transmission made a huge difference. It still was stalling, but my friend that owns a shop began working on the timing belt, adjusting the throttle body for idle, and rotating the distributor ever-so-slightly.

It now runs for 30 minutes without a stall and drives like you wouldn't believe. There's no knocking or shorts or sputters.

So now we've just got fixes to the EGR Tube and we talked about repairing it but then talked about bypassing the entire EGR system. I'm going that way and removing the EGR/Catalytic, etc and making it a straight tube to the exhaust out the back, replacing all of the corroded stuff.

The nice advantage is of course removing all of the EGR tubes, capping off the points that need to be, and replacing the pump to the EGR with just a dumb pulley to keep the serpentine in the same configuration/legnth.

After that, it's an oil change and then back to a Firestone alignment (lifetime). Hoping it'll drive like a champion for awhile so I can head to Maine to go pick up a 9-3 Saab SportsCombi 2007 a gent is holding for me. But that's besides the point!! My race/sports car is a limited edition 2014 Mustang, #8/50 Warrior v8 GT. SportsCombi will be a Winter/Summer driver and for ski trips as well as uber or lyft driving.

The only concern is that the oil is dark (as in transmission fluid went there) which makes sense because it's under 1K miles since the last change AND the AOD transmission came out with only 2 quarts in it. I've not had any visible streaks or red spots anywhere, and I'm in the North so during the Winter it's pretty easy to see the leaks. I never had any Faygo Red Pop spills in my driveway.

So, given we've got the vehicle driving and running smooth again, what could be causing transmission fluid to go into the oil? I know why the fuel smell was in there, but that should not have made it so dark so I'm leaning towards transmission fluid in there too.

I'll have to get pics up of Red IX at some point now that it's nearly done. It needs some cut-outs installed on the back wheel wells and a new paint job again, but overall it's a nice truck with some serious suspension modifications.
 

smokey

Hitech hillbilly
Staff member
I doubt it's transmission fluid in the oil.
The gas in the oil is just cleaning all the oil passages of old oil. The oil needs changed and the filter. The gas could break loose crud in the engine and plug up the screen on the oil pump also so watch your oil pressure.
 

Kaajot

Micro Machine Manager
I doubt it's transmission fluid in the oil.
The gas in the oil is just cleaning all the oil passages of old oil. The oil needs changed and the filter. The gas could break loose crud in the engine and plug up the screen on the oil pump also so watch your oil pressure.

Oh cool, so that's actually a good thing while I'm not driving it. Will be doing an oil change this week.
 

Kaajot

Micro Machine Manager
Update 4.9L

Not so great news:

The truck is again stalling at idle when started cold. It will continue running if you put in some RPMs, and once it's hot it stays running.

I'm waiting for the mechanic to put a tester on there to monitor the computer's data including temperature, fuel, rpms, etc. He already used a timing light to watch the belt, seemed to be fine.

An old greybeard mechanic I know said there's a coolant temperature sensor that reads to the system gauges and to the computer for its operations. This truck had been running rough in the Winter, but not this bad, and it was much colder then but I still had high use of fuel.

Could a coolant temp gauge be reading to the gauge that it's ICE COLD in the now HOT TEMPERATURES, hence the stalling and flooding of the fuel into the oil because it's running very rich?

Still have to check the TPS and IAC since we're now back to symptoms. Then the ECM if those turn up empty.



Beyond the things going wrong at idle, we've tested for vacuum leaks and carb/manifold leaks. Nothing is wrong there.



Also: Since the EGR Tube is broken at the Cat Converter, I'm mulling around the idea of cutting the Cat Converter out (it's a 1992, I'm not moving to Cali, it'e legit everywhere else) and putting a straight pipe in and removing the entire EGR system. However, I don't want to have a check-engine light for EGR the rest of eternity. I do like the gained space in the engine bay by removing all those tubes and the pump (Replace with a dumb pulley?)

The question there is that I've been told there is an EGR Delete/Eliminator that will fix the computer's error readings on the EGR once it's removed. Also looking for the pulley to replace the EGR air pump (I think that's what it is) so I don't change the Serpentine Belt's original configuration -- want to keep that standard for easy replacement and maintenance.

Where would I find a good EGR Delete/Eliminator and Pulley (or a kit?) for this operation?

Should I cut out the Cat Converter during this for straight pipe, or plug the cat conv to egr tube hole? It's going to have to be dropped anyway, so I thought it might be better to just remove the cat converter and put pipe in up to the manifold.

Is there a very good reason NOT to remove the EGR or Cat Converter, or will the delete/eliminator not stop the computer's error codes once the EGR is removed?

Thanks for playing 20 questions! :nana: Input appreciated. smiliepopcorn
 

Kaajot

Micro Machine Manager
Update 5.0 -- More bad

Hi All-

So, the truck is still not running and sitting in the shop.

The mechanics finally put a good machine on to read performance issues. The coolant temp sensor read -40 degrees apparently when they first cranked it over and the system (EGR?) read Closed. Then they restarted Red because she was running rough and it has read 248 degrees and fully open on the system.

Meanwhile, I convinced them to do a TPS check and we didn't even get to testing the TPS because the wire connector's voltage on the power (not ground or sensor) read .5v instead of 5v on the multi-meter.

So that's where we're at.

We also put the new Spectrum Premium distributor into the truck but that actually worsened her performance.

Meanwhile, I'm getting the easy stuff fixed while they work on the wiring. I've a leak on the side of the engine (driver side) in a box -- something about it being a valley lever or lever valley panel? I'm trying to find the part for my 4.9L L6 engine to replace the gasket on that pan so oil stops dripping.

I'm also looking for the EGR tube to hook back into the Cat converter. Any ideas on where to find the right part and what's a good stock/place to pick one up from? I'm not going to do an EGR delete.

Biggest problem is the missing 5v test on the TPS hook-up from the wiring harness. It read .5-.7v and that was it. Any ideas??? smilienothingFunnyto

Seriously need an idea. I'm maybe going to pull the ECM out and inspect it, but one of the mechanics next door to the shop (two shops) said it would be a transistor on the ECM and not an easy-to-repair capacitor. I still think it's worth looking at the ECM since we're now at a wiring problem.

The gents said they also tested the coolant temp sensors and they checked as good, although they were throwing bad temperatures to the testing computer readout. I've no idea how to interpret that -- ECM again possibly giving all kinds of bad output based on the problem, whatever it is?

Really a bit lost while I do the easy oil leak fix.

Going to do a Heater Core swap (new) if she's still down next week. Any pointers on that appreciated!
 

Kaajot

Micro Machine Manager
Also

It looks like the EEC-IV (ECM) may be a good check for 5v continuity issues if there is no reason to suspect any particular wiring?

I found a thread from another forum -- looks about right. Opinions? Aholes? Marco? Polo?

https://www.fordf150.net/forums/viewtopic.php?t=98880
 

Kaajot

Micro Machine Manager
Dear Diary-

I'm 99.99% sure my EEC-IV (ECM) is the demon. Please rid me of this temptation.

Much love.

-Kaajot

PS: If I do not reply again, you know the Devil hath me.
 

Sparky83

Virginia Chapter member
5,566
219
Norlina NC
sorry mate... thought when you had it running again i quit checking the thread thinking others were congratulating... but really couldnt say whats causing the issue... wish some of the old techs would pop back in.. we use to have a few really good ones..
 

Kaajot

Micro Machine Manager
ECM Pictures Here (EEC-IV model type AB on 4.9L automatic)

sorry mate... thought when you had it running again i quit checking the thread thinking others were congratulating... but really couldnt say whats causing the issue... wish some of the old techs would pop back in.. we use to have a few really good ones..


Thanks Sparky!

No worries, I remember 2 years ago having issues with the original engine and transmission swap and getting a lot of help from the older techs that were here almost daily.

So I've got the right ECM model (4.9L automatic ending in AB) and can get it at RockAuto, new, for about $98 so I'm going that way. I can also get the egr tube from them and seal up my cat converter, so happy about that!

Here's a few pictures of the EEC-IV (ECM). There's delamination on the lower pin. The techs at my friend's shop were afraid to unsolder it because they're not used to this, so I'll probably have to do it myself tomorrow to take a look at the more-important side ie capacitors, etc.

Hopefully the new ECM will do the trick. She runs real rough now and dies almost immediately after start-up. Throttlling keeps it alive but black smoke from the gas dump is non-stop.

The only thing left to do is possibly throw 14lb injectors after she stays running without stalling and remove the heavy flow from the 19lbs. I found some remanned bosch (set of 6) on ebay for about $83, but the guy says they're a 4-hole type and I don't know how many are actually in my current 19lb type. Any ideas on how to tell without opening up the top of the injection cover?

-K

PS: Also still have to fix the galley lever cover seal, but that is an easy job apparently -- will do with the oil change, also ordering that seal from RockAuto for I think $13. Not too bad and will get rid of the oil slick on the driver side of the engine block.
 

Attachments

  • 51985034451__16B0D875-E0B6-4159-B566-A50897252B87.jpg
  • 51985041156__415BB330-1205-4153-A3E1-2B34CB50658E.JPG

Ford Truck Articles

Top