Title says it all, really.. 3SGE, auto This only just started happening very recently.. At start up the car will sometimes drop in revs, and just cut out. Happens every so often - not at every start up. After getting going, and idling at lights, etc. this isn't an issue at all.. No drop, sits solid. The other issue is fluctuating revs while cruising, with no acceleration (ie downhill). It'll surge ~500 revs up, and back down, continuously. The car does actually accelerate while this is happening (not the gauges).. This happens on occasion, not always. On top of this (and maybe unrelated) a "rattle" has just shown up, purely while accelerating.. Any ideas?
Simple stuff first; I'd check the pipe going from the airbox to the throttle body for cracks, and clean the airflow meter, see if that helps.
Yep, both done.. I do have a missing clip on the air box - but it's always been missing.. I believe the seal is good. Might try out a temporary fix before I grab a clip, and see if anything changes. What else should I check out?
No codes.. I've suspected issues with the TPS.. voltage reads ~.48-.51v closed to 3.8v throttle completely open. It raises with the throttle opening, no fluctuations.. I'm worried about the 3.8, shouldn't it peak higher?
Pins on the TPS from top to bottom are: VC VTA IDL E2 Measure resistance between VTA and E2. it should be between 0.2-0.8 kΩ Between IDL and E2 with a .5mm Feeler gauge between throttle and stop screw should be less than 2.3 kΩ Between IDL and E2 with a .7mm Feeler gauge between throttle and stop screw should be Infinity Between VTA and E2 with trottle fully opened 3.3-10.0 kΩ Between VC and E2 it should always be between 3-7 kΩ Adjustment of TPS: Insert 0.6mm Feeler gauge between throttle and stop screw. connect terminals to IDL and E2. Loosend screws and slowly rotate sensor until ohm meter deflects. then secure with screws Then recheck continuity between IDL and E2: with 0.5mm feeler gauge there should be continuity with 0.7mm Feeler gauge there should be NO continuity.
I had a similar issue with my alltrac. after the TPS was adjusted it still fluctuated slightly. I found that removing the throttle body and cleaning it, along with cleaning the ISC valve on the bottom of the TB made a HUGE difference. Start by adjusting the TPS. if that doesn't help I can post up how to test the ISC valve. Is the hose from the ISC going to your intake? does the issue persist after the engine is warm?
Thanks, awesome info.. I'll get on it when I have some free time and post how it goes :thumbsup: Yep, revs fluctuate even when the engine is warm.. I'll need to suss out the ISC
If it's doing it when warm it is probably not the ISC. The ISC has a coolant feed and only opens when the engine is cold. I would start by cleaning the inside of the TB the best you can with it still on the car. if there is something causing it to not close all the way that could cause the issues you are describing. Then move on to TPS adjustment. Good luck TPS adjustment SUCKS!!! its so touchy! lol
Is there any play on the tb butterfly......mine does this and I have play....just haven't gotten around to swapping it out for a new one yet.
Nope. Just a little more info.. The stalling happens regardless of if the car is warmed up or not.. Just purely at startup.. Also, in regard to the rpm fluctuations.. It'll only happen in gear, not neutral. Still yet to check out the TPS - figured I'd throw some more info up until I get the time
So just a little update on this... Not stalling on me anymore... Thinking I got a dodgy tank of petrol..
