i've been reading this post for the past two years getting more and more hooked and finally i have what i've been hooked to. couple problems that i have with it though. it has 97,000 miles with a couple bolt ons. fp, adj. fp reg., fp guage, hotwire kit and volt booster, hd oil pump, hd valvesprings, and some braces...no chip. i have a rinky dink scan tool (some OTC thing..got it from a friend) the car is set currently with 43 lbs of fp. i get anywhere from 1 to 10 degrees of retard. the car also has a slight surge at wot. nothing audible, i can just feel it. the car pulls hard, it just surges. the fp guage is the underhood type so i don't know if the car is holding pressure. the car also has a tendency to idle very high all of a sudden (2500rpms). it is random for the most part but sometimes seems to be related to the tranny being shifted from neut. to drive. i don't have a boost guage so i can't help you there. i have adj the tps to .44 and 4.86 at WOT. i have also cleaned the iac in hopes of fixing the high idle. all in all the car is great and i love driving it. much more fun than my old rustangs. please help me out here guys, you do a wonderful job with everyone else and i thank you!
Nothing wrong with an OTC scan tool. Try pricing a new one to find out just how rinky-dink they are.
I would start by using your OTC to see if the P/N indication is correctly changing as the car is taken in and out of gear. If not, this might be part of the problem.
Scott,
thanks very much for the reply. the scan tool i have is not the OTC 2000 or 4000. i borrowed it from a friend and he said he really only used it for setting the TPS and taking trouble codes. he told me not to bank on it. that's y i said 'rinky dink'. what exactly is the P/N indication. is that the same as the PROM ID#. if it is it is 3676 and it never changes...at least i dont think it does. also, in the meantime i changed chips from a red armstrong to a older kenne bell with no changes. i tried cleaning the IAC valve but that didn't help either. so, every once in a while the car will race when im stopped at a light. not very fun when a 300 hp car learches towards the bumper of a 500 SL. kinda gets the heart racin'. i don't know what else to check. maybe the computer is acting up??? let me know what else you guys can think of.
maybe the o2??????
TIA,
damian
High Idle: I notice your tps is at .44. This is borderline high, so try it lower, say .40
If that doesn't help try setting the IAC per instructions posted this site.
Surging: If you've been reading this list for two years you probably know the importance of fuel pressure vs. boost. Have you checked that with an _accurate_ pressure guage?
If the ecm is pulling 10 degrees timing you'll feel that too.
P/N refers to the 'park/neutral' switch indication to the ECM.
The idle may also change depending on the temperature the Mass Airflow Temp (MAT) sensor in the intake tract sees. If that sensor or wiring is damaged, it could be a factor.
You will need to check for what numbers from the scan tool seem to change when it begins to 'race' like that. There's likely a simple cause if you can get some data about what happens when that condition starts.
thanks for all of your help. ill start playing around with it when the weather turns. thanks again.
damian
one more thing. i check the site and i couldn't find where to adjust the IAC. i did clean it but i have not idea how to adjust it. let me know or send me the link.
peace,
damian
The link is under Technical Info, ECM and Sensors:
http://www.gnttype.org/techarea/faq/IACreset.html
thanks scott,
i took the car out for a ride last night and sure enough, it did it again. but this time i kept an eye on the IAC counts. when the car was hot and at normal idle the IAC count were btw 10 and 50. when the car would race they would shoot up anywhere from 80 to 130. so i guess that is my problem. thanks for all of your help. im sure ill have more questions.
damian
i just reset the IAC motor and the same problem occurs. when the car is put in drive the car idles high. by high i mean 950 to 1100 rpms. and the occasional rev while at a stoplight. when this occurs the IAC counts are about 100. maybe the IAC motor is bad...not sure. i have been keeping an eye on the o2 volts and they seem to fluctuate while at idle (anywhere from .200 to .750). at wot they are stuck at .800 (im happy with that) fp set at 43 lbs static. also while at wot black smoke pours from the tailpipes. way more than usual. not sure if that is normal for these turbo cars. on my last pull the ecm pulled about 4 degrees out. i thought that was odd since the o2's were so high. oh 94 octane in the tank. like to figure this car out. HELP!!!!!!