Help Please!!!!

[Bronco_bill]

4.0 Surges, Stumbles when I push the gas quick, has a slightly high idle, and has an intermitent fuel smell out the exaust. It smokes like hell + runs/smokes worst in the morning. About 55 K on engine.

Just changed all the plugs, all the old look perfect. New TPS, fuel pressure reg, PCV, air filter, fuel filter, O2, cleaned MAF. It runs worse with the new IAC so I put the old back on. Can't find any vac leaks no oil or coolant loss. Don't know what way to go next. Please help!!

 

[toad]

I would have said fuel press. reg. but youve done that.
fuel pump? but that shouldnt make it run rich like you say.
Sorry not much help, but sounds like my 92 when regulator went south.

 

[Opera House]

Put a pressure gauge on the fuel rail

If it is not the fuel pressure regulator leaking, it is a fuel injector. Should easily hold pressure for 15 minutes with the engine off. Pulling the plugs should give you an indication if which injector it is.

 

[Bronco_bill]

I was thinking also a leaking injector they do have about 300,000 on them. The problem is the plugs look like they a burning fine. Maybe let the truck sit over night and pull the plugs one by one to see what cyl smells like raw fuel?

 

[Bronco_bill]

I just bought a set of new injectors pos is still not fixed! The engine runs better but I think it still smells like gas out the tailpipe. Don't know what else to try? It runs smooth but when I push the gas the engine speed revs up and takes way to long to come back down. The stumble is about gone.

 

[Bronco_bill]

New intake gasket, new crankshaft sensor. No egr or cam sensor on the truck. Runs good but still dose not idle correctly. I guess the only other parts it could be is fuel pump, pluged cats, or bad computer. Anyone have any thoughts before I have to hold up 7-eleven.

The new injectors are awsome!!! I bought the high performance set from FiveO motorsports for $180. The difference is amazing. It is so nice to have the ability to pass people going up a hill.

 

[Bronco_bill]

Thanks for ALL the help!!! 158 people looked and only two people tried to help. Thanks again.

 

[MrShorty]

Sorry your problem isn't fixed. Allow me to be #3 to chime in.
Did you ever put a fuel pressure gauge on it to see what the pressure was and to verify that it would hold pressure?
Did you ever check the operation of the injectors? A bad ground could cause an injector/one or both banks of injectors to get stuck open too long.
Have you ever run the EEC-IV diagnostic tests? The PCM is responsible for controlling the mixture by controlling the "injector pulse width"

 

[Premier]

Originally posted by Bronco_bill
Thanks for ALL the help!!! 158 people looked and only two people tried to help. Thanks again.

Title says pleas help. So I looked, but dont know how. Sorry

 

[Bronco_bill]

Thank You! I cant begin to explane how frustrated I am at this point.

Was tring to avoid buying a pressure guage but I guess it may come down to it. Right know I am thinking the fuel pump might be bad since it kinda make the whine noise that others have described and is the only fuel delivery part that has not be replaced. My other thought is that the 5 speeds uses a differnt TPS than the auto and the Autozone universal dosn't work for me
Symptoms now: Cold start it smokes and smells like gas out the tailpipe. Rough/no fast Idle. When it warms up it idles at 1000 but smooth. When I rev the engine quick it sometimes stumbles going up in engine speed and takes to long for the engine to slow back down. Unless the fuel pump can cause these symptoms it seems to me that the computer may be bad, but my past experence has shown me that they are reliable. I will check for bad grounds.

Thanks

 

[Bronco_bill]

No codes came up in the diag. Replaced all injectors with brand new ones and I listened to each with a stethascope. All sound like they are operating the same.

 

[twomedicine]

Fix Or Rebuild Daily

Geeze, you are really having a bout with that thing. Going into overtime...hope you win

I had only but one thing come to mind or maybe two. Is there an air temp. sensor that would send info to the computer to richen the fuel during start-ups and cold weather? Sounds kinda like and old carb. problem, like the stuck choke.

And no vacuum leaks into the intake?

Too bad you couldn't have cut your losses short earlier and taken to a Ford mechanic. Maybe it's displaying symptoms that they are familiar with//

2med

 

[Bronco_bill]

New fuel pump. It runs very good but is still not right. I think it still takes to long for the idle to come down after steping on the gas. With the TPS unpluged it responds like it should, any thoughts? I checked the grounds all seem good. I am out of ideas seems to be that the only other thing it could be is the ECU.

 

[Nate1]

What is your TPS voltage when it is closed (it should be .96v) and does it evenly progress as you open the throttle up to 5v? If not, something is amuck.

 

[Pete]

OK, looks like you tried the IAC so ignore my other post.

There is an air charge temp sensor in the lid of the air box but, I am thinking, if it was no good then wouldn't you get a code?

You can take it to a muffler shop and have them do a pressure drop test across the cat to see if it is plugged.

A fuel pressure test rig is about $40. Did you try that yet?

You might want to get an OEM TPS and try that. I had that problem with the fuel pump relay - AutoZone had about 4 different ones that were supposed to match. I finally had to get an OEM one.

 

[Pete]

Are you still having the rich cold-starting problem? You said 'it runs very good but is still not right'. My Ex does the same thing when closing the throttle; when coming up to a stop, I push in the clutch and the engine doesn't slow down to idle untll I've been sitting there about 2-3 seconds. Besides that it runs fine.

 

[Bronco_bill]

Put on my old original OEM tps and it responds the same way as the autozone so I think I could elimate it being a bad part. Still haven' checked the fuel pressure yet I figured that for the cost of it I just as well should put that money to a new part since they were all original but i guess I am getting to need to buy to eliminate. I am going for a good test run so I am going to reset the ecu again today and scan for codes when I get back. I will also test the TPS voltage. It ran good after the fuel pump install but last night i took it out and it seemed to run not so good. I will post my findings as well as symptoms tonight. Thanks for the sugestions.

 

[dogfriend]

Your high idle is likely to be caused by a vacuum leak, since replacing the IAC had a negative effect. I would make sure that the gasket for the IAC is in good condition. If you have extra (unmetered) air coming in, it will raise the idle speed. Your idle speed should be about 750 - 800 in N with a warm engine.

 

[lonestar]

I been trying to track down a TPS code for a couple of years now. It's on my older escort I had before I bought my X, now I am getting a TPS code on the X too, but the TPS checks out fine (voltage and resistance).

Replaced TPS and ISC on escort and am still getting same code. All sensors seem to check out, MAF, O2, ISC, TPS, EGR. And the problem is intermittent. Will run fine for days and then I will start getting racing or sticknig idle when I come to light, the idle just doesn't return. The ISC seems to hold open the throttle for some reason. Even tried $20 ECU off ebay and it does same thing. I'm frustrated.

Maybe Autozone is selling faulty TPS sensors?

 

[YourmamaISSOL]

the only thiought i have a t the moment,,,,

.have you check the throttle cable... ford uses a spring to have the trottle return to normal after hitting the gas mybe it sticking or has lost its spring .. the spring is meshed with a throttle posistioner plastic bracket could have broke.

thats all i have because it looks like you have replaced every thing else...

Gary