Has anyone considered one of the following to be the culprit?

TP Sensor (Throttle Position)
MAP Sensor (Manifold Absolute Pressure)
IAT Sensor (Intake Temperature)
IAC Valve (Idle Air Control)

I also has for 40 minutes idling in drive in drive w/ ac park with a/c
park w/o a/c then shut down for 30 sec restart in an attempt to reset the IAC valve pintle since I disconnected my battery for my plug/wire install. This was of course no help either.

So if anyone changed any of the above & had any success with it
please let me know. My idle, surge and stumble is the worst ever since my little tune up, fustrated to say the least to have such poor results from what should have been good thing.

Thanks again, sorry for the long post....

 

Most sensor problems can be identified by monitoring with a scan tool. It takes a little knowledge to know what they are supposed to read. Hesitation/stumble problems seem to be the hardest to find because so many different things can cause it. That is why the scan tool can help rule things out and/or direct you to a source.

 

Thanks for your reply Shoebox.

I guess I'm going for the "needle in the haystack" method, I don't have a scan tool.

I guess it could be any of the above I mentioned huh?

 

That's the problem, it could be most anything. An OBD-I scan tool is not all that expensive and can save you time and from replacing good parts. For me, I just cannot work on modern cars without some diagnostic capability. If you have a computer or laptop to use, a special cable and some free software will do the job.

 

u dont have to replace the IAC. well, u may....but, u can also take it out and clean the valve itself and the housing with carb and choke cleaner. it is free, so it cant hurt anything. i am going throught the same thing right now.

 

I'll try that, maybe we can keep each other informed on progress.
Thanks

 

I pulled the map & iat sprayed them down & cleaned them up real good. No help.

Shoebox - I had a mechanic friend of mine hook his diagnostic computer up to the car (amazing tool, couldn't believe it has windows xp on it) we went through the whole list. EGR MAP IAC ecm pcm spark all check out ok, km ok etc. The TPS voltage was wacky so he is confident it is that. Last night I ordered the MAP TPS and IAT sensors, only $50 from Sam Taylor. SO when I get them I"lll swap and he will scan & calibrate for me.

You were right about having the scan done. Put my mind at ease for now, thanks.

Wish me luck

 

Have you checked and thouroughly cleaned your PCM and engine grounds?

 

Hey guys and gals,

I changed my IAT sensor in the intake elbow this morning and after she got heated up past 220* I had a smooth idle, and no surge in my lower rpms, first time in a long time,

$10.00 part from Sam Taytor, worth a shot?