High Idle w/ fuel smell.

cougarxr7

Registered User
Driving the other day, car starts idling high.
Changed the IAC and dis, problem still persists.
Started, and ran car without IAC, and TPS connected idle still high.

Which brings me to the raw fuel smell.
This problem has been going on for sometime.
The IC tubes and the fuel injector 0-ring, are the only places
I can think of that fuel smell could come from.
Could this fuel smell, and high idle be related or more likely 2
separate issues?
 
Driving the other day, car starts idling high.
Changed the IAC and dis, problem still persists.
Started, and ran car without IAC, and TPS connected idle still high.

Which brings me to the raw fuel smell.
This problem has been going on for sometime.
The IC tubes and the fuel injector 0-ring, are the only places
I can think of that fuel smell could come from.
Could this fuel smell, and high idle be related or more likely 2
separate issues?

Good afternoon


A damaged fuel pressure regulator line, the charcoal purge solenoid (located under the passenger side front bumper cover) vacuum hose and or the fuel pump sender/tank seal would be the first places I would investigate for raw fuel smell. The charcoal purge solenoid and a fuel pressure regulator line vacuum leak(s) could also cause a high idle. Have you pulled any codes?
 
Sam - I have a similar smell but only after some higher RPM higher speed driving. Do I need to perform any inspections??? Does this charcoal get saturated?
 
Sam - I have a similar smell but only after some higher RPM higher speed driving. Do I need to perform any inspections??? Does this charcoal get saturated?

Good morning


I had not seen a 1989 - 1993 thunderbird fuel charcoal canister saturated. However I have seen solenoid purge valve the rubber vacuum hose(s) cracked and or deteriorated. Sometimes rough/rolling idle can be traced to this component area.

In your case I would jack and support the front end and "sniff" smell around fuel charcoal canister area after high rpm driving. The canister purge solenoid signaled by the EEC for operation usually during cruising. Maybe this is why you noticed the fuel smell after shutdown. Inspect the hose connector(s). If the fuel smell is not present, lower the front and jack and support the rear. Start the car and smell "sniff" around the fuel tank area mostly on the fuel filter passenger side. Could be the fuel tank vapor rubber vacuum hose connector and or the fuel pump assembly O-ring gasket. Unfortunately the tank will have be dropped/lowered for the repair.

See attachments:


https://www.google.com/url?sa=i&rct...L5Kbi-ELldanC2im2mJzPqLg&ust=1496563949176369


http://www.tccoa.com/articles/mn12parts/fuel-pump/fpk-install/DSC00034.JPG


http://www.tccoa.com/articles/mn12parts/fuel-pump/fpk-install/fp-wiring.JPG





Good Luck.
 
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Does this charcoal get saturated?

Not likely without a major fail you'd notice from other symptoms, such as raw fuel in that area; more often it's a solenoid and/or plumbing issue. Can also be from an accident to that corner of the car where component damage went unnoticed, perhaps. But if it is flooded w/fuel, best to replace.

Code for evap solenoid failure, however (they fail outright, get stuck, wiring, etc.) is 85 or 565
 
Sam - thank you as always. You seem VERY pro.

KMT - HAH, I do recall the car was hit on this side and the previous owner had it repaired at the dealer. Wonder if they overlooked something?
 
Thanks for replying!
I'll check for codes but I thought, "no engine light, no codes".
Need to generate some, disconnected the battery.
I will run some tests.
I will check the charcoal canister system.

Hey pots, how's Oregon! Can't wait to hit that lottery, I am moving to Oregon!
 
Not sure, but with big money, I'm sure I'll find a few to live in!

I got the canister purge valve off.
Does anyone know if you can ohm it out to check if it is good?
I need to check out how that system functions.
 
I got the canister purge valve off.
Does anyone know if you can ohm it out to check if it is good?
I need to check out how that system functions.

Did you get around to checking codes? Any evidence of raw fuel?

An ohm check should confirm it doesn't present an open circuit. Do a visual inspection for corrosion, damage etc. Blow thru it or vacuum test and it should be closed when off the engine. You can try putting 12v. thru the connector to see if the solenoid shunts and opens the port. Replace if in doubt since you're already that far in.

Vacuum test the canister to confirm it isn't leaking. Inspect the lines coming in for cracks, damage etc.

Check codes when done to confirm.
 
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Thanks KMT!
Everything looks good.
I will check everything like you said!
No I did not pull any codes, I thought no engine light, no codes.
 
No I did not pull any codes, I thought no engine light, no codes.

Ford's EEC often holds back throwing a light for every incident, so don't think there is nothing to check for just because there isn't a light. There are various tests: KOEO (key on engine off), KOER (key on engine running), and Continuous, or stored, memory codes. Running codes can help pinpoint issues and save time as well as money by not guessing/throwing parts at a problem you don't understand.
 
I could not get codes, idle out of range.
I am going to try a different IAC, I have a few. Need to try and get the idling correct.

If the EEC can not obtain control of engine speed/idle then would the cause of high idle be mechanical?
 
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I could not get codes, idle out of range.
I am going to try a different IAC, I have a few. Need to try and get the idling correct.

If the EEC can not obtain control of engine speed/idle then would the cause of high idle be mechanical?

Good afternoon


Failure of the body following (mechanical components) could cause the EEC to see un-metered air and or faulty signal resulting in a high idle:

- Sticking throttle body valve and or severely leaking shaft seals.

- Leaking throttle body to intake plenum seal.

- Leaking idle area solenoid seal.

- Faulty throttle position sensor or electrical connector.

- Cut and or damaged mass air flow sensor seal

- Driver side valve cover PCV line to the intake duct for damage.

- Damaged air duct (cracked and or torn) or loose clamps.
 
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***************UPDATE*********************
I fixed the high idle. It was the IAC, trashed the other 2!
Yet I am still trouble with gas fumes.
Ran codes, got 11, so no stored codes.
Engine running did not get code 85!

What are the chances it could be leaking fuel injector O-rings?
I seem to smell gas fumes most of the time!
 
>What are the chances it could be leaking fuel injector O-rings?

That is what finally chased down the smell issue to many years ago on a 280 ZX. First and last car that was not FoMoCo :)
Creighton
 
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