thank you for responding once again u give me alot to think about.
yes ican move linkage by hand.
it is like the car is telling me where it wants the idle to be so i did a little.but it still wants more.
as far as cam timeing i paid a well known guy alot of$$$ to do it right hope he did.
car runs perfect no DTS can tell the deff from old TB and new TB and yes car runs better with 52mm than with 58mm.
and this ploblem only happens when i keep foot on peddal at cruiseing speed.
have checked with likage on off it dont matter.have played with all the vacs to see if anything would change.did manage to stall it abunch.
have check every little thing around TB to make shore nothing hanging up.
on the 58mm i even put anouther spring on it just to see. and it still kept it high.dont get me wrong it is a little better with 52mm.
did not do this with factory TB would put back on but got danage when i took it of
seems like springs not strong enuogh ?just a thought doesent air pull the butterfly the same wouldent it want to keep it shut the same as open
Exactly !
Thats what I was trying to say in all the mumbling I was doing last night..!
Something else going on here...
Wheres base ign timing set? was that advanced too far and forcing a high idle? Did you try backing out of the timing a 2-4 degrees retard and see what happens. Basically ANY tuning process of odd parts is going to be a trial & error process....try this, try that. Stop when something works and FORGET what the manual says about the tune specs because the modified engine is not what the manual is/was written about.
Has the IAC been pulled out and checked to see if the pintle is bent or damaged>? if the IAC was screwed in and tightened with the pintle extended too far, it can bend it and the seal never happens letting idle AIR pass thru all the time. You don;t necessarily get a SES lite for IAC..(something else maybe) because the motor functions...its the seat thats AFU.
Look at the IAC pintle and always install those by the measurement in the package....that tells you the max it can stick out from the IAC body and not get damaged. Usually they are srewed in enough to mount ok but I have seen one that was too far extended and bottomed the pintle with a couple turns left on the IAC valve before tight.
Once installed and engine runs and goes thru an ECM cycle it will self adjust. Its not magic, it just keeps trying to go forward or back depending on what the rpm is and what the ECM thinks it should be...
And Johns got a good point....there are positive pressure EGRs and Neg pressure return EGR valves and they all look like each other. If thats not right, it could be leaking exhaust gases into the manifold causing a lean/air leak symptom. High idle is the symptom of air leaking.
Hows the PCV acting? is there good vac on the valve and line TO the intake? what about the hole in the valve cover? whats going on there...anything blowing OUT or does that have some vac? That should be fairly neutral with the crankcase maybe breathing in/out slightly with no PCV in the hole....the vac from the PCV should be what applies a good vac to the crankcase to pull all the fumes out and keep a mild vac under the pistons.
Check IAC pintle condition
EGR for operation and correct part per yr/make/model
check ignition base timing for too much advance
Beyond that....I dunno :confused
This may be simply a case of a slow or late IAC...hunting.
Mine has its own behavior as many seem to have.
When cold mine idles up to 900-1100 until eng temp reaches at least 130 then it settles to around 750-800. I can drive at that point IF I want. Then it will again drop the idle once the temp reaches 158...everytime. Now it settles down on 600 rpm steady. A warm start will send it to the 2nd tier idle of around 800 for 10-15 seconds then it settles down to 600 again. Depending on the temp of the engine, it will run idle up for extended times until it sees a temp that it likes. This can also keep the idle high IF I start driving too soon, it won;t let it idle down all the way until its hot enough.
So, 1 more thing to check....the eng coolant temp sensor in the front of the intake manifold....one is for cold start and has the wire run around to the driver side to the CS valve and the other sensor is the coolant temp sensor that tells the ECM whats going on. Check the connector for the temp sensor.
May as well consider the cold start as well. Check that and see what happens if the CS connector is removed. The ONLY other thing that I can think of would be a leaking CS valve...(if your model even uses CS 9th injector) If you DO NOT have cold start then your ECM handles cold start up by making the 8 inj richer for a few seconds...thats back to the temp sensors. When a temp sensor fails or the resistence is too far out of spec, it can fool the ECM into thinking the engine is stone cold all the time and it'll richen the fuel pulse to the injectors.
This is where a scan tool would be real nice to have.....
They still have them on Flea Bay. OBD-I & II compatable.
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