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Topic: Idle issues... need opinions. (Read 3659 times) previous topic - next topic

Idle issues... need opinions.

My car has been acting up lately... started with the nice weather, figures.

2 issues... 1 of them I can take car of but will mention. It could possibly aid in opinions.

1- (the one I can get checked out) Check engine light that can be resolved by turning the car off and restarting. Eh, gotta pull codes...

2- Idle problems. I will start off for work without an issue. Drive on the highway at... well lets say the speed limit. When I hit the off ramp and back to city driving my idle stays up around 1,000-1,200rpm. Normal idle for my car is 700-800rpm. Starting yesterday I noticed another issue occuring, my idle is "sticking". Leaving the parking lot at work I shift out of gear to stop at an intersection, and the idle stayed where I had it in gear (2,000rpm), it did the same for the next 2 intersections. I shut the car down and restarted and the issue went away.

I guess what I am asking is, could this issue be associated with the computer? Spew all your knowladge at me!

Re: Idle issues... need opinions.

Reply #1 –
my TC did the exact same thing, change your TPS
It's Gumby's fault.

Re: Idle issues... need opinions.

Reply #2 –
and on the same topic... anyone have a list of eec4 codes for an 89 mustang computer??? lol

Re: Idle issues... need opinions.

Reply #3 –
My 85 Cougar did the same thing twice but problem was different the 2nd time. 1st time TPS. 2nd time two problems linkage occasionally stuck fixed with a little lube and one of the temp sensors came out on trouble codes. Replaced, no more problems. I think your on the right track with the trouble codes! Best of luck.

p.s. I think I have those codes but can't post now... later today perhaps...

Re: Idle issues... need opinions.

Reply #4 –
Pulled em...
Old codes in memory durring the KOEO test:
-26 MAF out of range (I disconnected the MAF a while ago)
-43 HO2S Sensor not reading / Lean @ WOT for 3 seconds or more
-51 Engine Coolant Temp (ECT) signal too high
I reset the codes and did not get any durring the retest.

KOER Test:
-12 High RPM durring test
-44 air system inoperative (right side thermactor)
-94 air system inoperative (left side thermactor)




I was told to clean out the IAC with a carb cleaner and see what happens... and that the 94/44 paired codes are nothing to worry about because of my setup.


Here is the site that I found all the info on. The site contains all the procedures for KOEO, KOER, Cylinder, and wiggle tests and also has both 2 and 3 digit code reference charts.
http://www.dalidesign.com/hbook/eectest.html

Re: Idle issues... need opinions.

Reply #5 –
2- Idle problems. I will start off for work without an issue. Drive on the highway at... well lets say the speed limit. When I hit the off ramp and back to city driving my idle stays up around 1,000-1,200rpm. Normal idle for my car is 700-800rpm. Starting yesterday I noticed another issue occuring, my idle is "sticking". Leaving the parking lot at work I shift out of gear to stop at an intersection, and the idle stayed where I had it in gear (2,000rpm), it did the same for the next 2 intersections.

I'm having same or similar symptoms, but don't get any codes. I don't have a tach, but can definately feel a difference in RPM's at idle after driving @35 miles to work on highway. I notice after driving for a good distance that it develops a vibration in the idle once I stop at a light or something. Enough that the passenger seat is shaking. I am still learning the ways of this car, and wondered if I was just expecting a little more from it than what is normal or possible with 167,000+ miles.

Tbird232ci, TPS same direction for me as well??

Re: Idle issues... need opinions.

Reply #6 –
Here's a temp. to resistance table for the ECT.

212deg F - 2.07k ohms
140deg F - 7.70k ohms
86deg F - 24.27k ohms
68deg F - 37.30k ohms

                              JP :welder:

Re: Idle issues... need opinions.

Reply #7 –
I cleaned out the IAC yesterday, it was indeed gunked up with a good amount of carbon. Idle issues have calmed down a bit and I drove back and forth in traffic around town. However when I went to go from the firehouse to my house the idle was again running high, but not until the end of the journey. I did race it and was being stupid the whle way, I hope it was just because of that.

I must run some errands today, and I am going to replace the ECT sneding unit and see what happens.

Re: Idle issues... need opinions.

Reply #8 –
Replaced ECT... had to get a 1" deep socket to do it, didn't have one.

Pulled codes again in the KOEO test:
All memory codes
-14  Ignition pickup was erratic
-33 EGR did not open/ respond during test or if memory code, did not open intermittently

BTW, idle is still high, now it seems to enjoy 1,000-1,100 RPM...
I'm gonna look for my spare TPS in the garage...

Re: Idle issues... need opinions.

Reply #9 –
youre going to need a meter to change your TPS, because youll need to reset the voltage
It's Gumby's fault.

Re: Idle issues... need opinions.

Reply #10 –
Uhh... you know there are several temp. sensors and there's the wiring issue. Bad wires or changing the wrong sensor can lead to a very frustrating experience. I've made this mistake before :disappoin . Break out the Volt Ohm Miliamp meter take some resistance readings. Don't have one; Get a cheap one at Radio Shack, it'll pay for itself a hundred fold.

This is getting interesting looking forward to your next post !  Best of luck..

                              JP  :welder:

Re: Idle issues... need opinions.

Reply #11 –
Quote
This is getting interesting looking forward to your next post ! Best of luck..


Thanks, that gave me a laugh.

That one sender was the one that I got a previous code on, Ill see if it shows it face again.

I must go and get a meter, I'll see what happens with the trip to work tomorrow... how it acts and all. If it still bothers me I will get the meter, find the spare TPS, and install that bugger.

Re: Idle issues... need opinions.

Reply #12 –
You've already replaced the ECT, but here's a spreadsheet where you can find if the ACT/ECT is reading correctly. Input a temperature to find the correct Voltage/Resistance. Use "goal seek" to find a temperature from a recorded Voltage/Resistance. I created it yesterday while trying to solve my EGR bucking issues.

Re: Idle issues... need opinions.

Reply #13 –
After I got off-line last night I got to wondering. Does your ride have air conditioning? What happens  when you turn it on? RPMs should increase. What happens when you turn it on, hood up, so you can get at the compressor and pull the cycling clutch switch wire off while its running (it's the wire on top of the compressor on my 5.0.)
In this condition the the rpms should drop, because the compressor is no longer being driven. If that happens, try the procedure when it's acting up. I would like to know the results.

Jeremy advice is very good, wish i'd wrote it. I would like to add, make sure there's no voltage on the wire or device before making resistor checks and read the meter booklet thoroughly. Your meter will thank you for it.

JP :welder:

Re: Idle issues... need opinions.

Reply #14 –
checking the TPS would be ideal...
It's Gumby's fault.