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Yup, more idle problems

  • Thread starter Thread starter dz01
  • Start date Start date Jun 29, 2018
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dz01

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#21
  • Jul 10, 2018
  • #21
Mstng93SSP said:
You sure you have no codes? When my engine coolant temp sensor went bad it caused a high idle, but I had a code (I think it was 51).
Click to expand...

Key on engine off and key on engine on both clear.
 

jrichker

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#22
  • Jul 10, 2018
  • #22
No code 11 (two flashes when the computer dumps the codes)? A perfectly functioning system will always get a code 11, it is the everything is OK code. The 11 code is computer passed its internal self test.
If you don't get an 11, you have computer or wiring problems.
Please check and repost.
 
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dz01

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#23
  • Jul 10, 2018
  • #23
jrichker said:
No code 11 (two flashes when the computer dumps the codes)? A perfectly functioning system will always get a code 11, it is the everything is OK code. The 11 code is computer passed its internal self test.
If you don't get an 11, you have computer or wiring problems.
Please check and repost.
Click to expand...

Yes, did get 11 indicating everything is good.
 

dz01

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#24
  • Jul 16, 2018
  • #24
I finally had a chance to take the car out for a spin after testing the volts on the TPS. I wanted to make sure and drive it before tweaking anything else so I could get a new baseline. Believe it or not, the minor adjustments I made to the TPS seems to have worked. I drove the car yesterday for about an hour. It was pretty hot outside and normally my idle would have started to hang within 5 minutes of driving and continued to hang until I shut the car off.

Coming to a stop with clutch in the RMPs dropped down to ~1K like they did pre idle hang, then within 2-3 seconds down to ~800. I've always had the drop to 1K right away then it takes a minute to drop to normal idle. Don't know if all foxes do this, but I could never seem to get my idle to settle right away.

I did notice the idle seem to drop lower than normal on occasion after driving a while (600-700), but overall seemed to run pretty good. I may put some more miles on it then adjust the idle a little.

This has gotten me curious to see if adjusting my TPS to the higher side of the range will result in my idle hanging again. Outside of testing for codes, the only thing I touched was the TPS and both my initial test and slight adjustment were both within range.
 

FastDriver

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#25
  • Jul 16, 2018
  • #25
Mike pointed out to me awhile back that stock fox bodies idled at like 675. So, I'd say it's where it should be.
 
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Black1987

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#26
  • Jul 17, 2018
  • #26
dz01 said:
I finally had a chance to take the car out for a spin after testing the volts on the TPS. I wanted to make sure and drive it before tweaking anything else so I could get a new baseline. Believe it or not, the minor adjustments I made to the TPS seems to have worked. I drove the car yesterday for about an hour. It was pretty hot outside and normally my idle would have started to hang within 5 minutes of driving and continued to hang until I shut the car off.

Coming to a stop with clutch in the RMPs dropped down to ~1K like they did pre idle hang, then within 2-3 seconds down to ~800. I've always had the drop to 1K right away then it takes a minute to drop to normal idle. Don't know if all foxes do this, but I could never seem to get my idle to settle right away.

I did notice the idle seem to drop lower than normal on occasion after driving a while (600-700), but overall seemed to run pretty good. I may put some more miles on it then adjust the idle a little.

This has gotten me curious to see if adjusting my TPS to the higher side of the range will result in my idle hanging again. Outside of testing for codes, the only thing I touched was the TPS and both my initial test and slight adjustment were both within range.
Click to expand...
Might be a dumb question, but have you tried lifting the gas pedal when it hangs to see if it drops?
Reason I ask is there is a spring on the throttle cable that can hang sometimes. Just a thought.
 

dz01

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Jul 18, 2018
#27
  • Jul 18, 2018
  • #27
Black1987 said:
Might be a dumb question, but have you tried lifting the gas pedal when it hangs to see if it drops?
Reason I ask is there is a spring on the throttle cable that can hang sometimes. Just a thought.
Click to expand...

I'll check that out, thanks
Just to clarify, my idle will hover at 1K as I'm almost to a stop, but not drop down further until I'm at a complete stop. I know others have said that's just how these cars run. This is not as much of an issue for me, but more of a question on how it should work.
 

dz01

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Jul 20, 2018
#28
  • Jul 20, 2018
  • #28
For those tracking this thread, I took the car out for a pretty lengthy ride yesterday. Car ran great! No surge at all. TPS adjustment, even within range, definitely had an effect on my car. Thanks for all the help.
 
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