chuckhusty

So, I recently had a starter replaced on my 1995 LS400 at a shop. (Reading through the threads on this forum convinced me that this was not a job I wanted to tackle on my own.) So, $700 later, the starter is replaced and the car starts right up. However, upon receiving my car back, it has been running worse than when I dropped it off. When the car is cold, it idles normally and seems to run as it did before the starter replacement. When it warms up, the idle starts fluxuating between 800rpms-200rpms sometimes idling so low that it stalls out. I've noticed that running the AC keeps the rpms up far enough that when it begins to dip, it at least doesn't stall out. So, I always keep the AC running. Also, the car rpms more normally when when in DRIVE. When in PARK or NEUTRAL, the rpms once again bog really low sometimes causing it to stall. Thus, I come to this knowledgeable forum in hope of some explanation/guidance how to remedy this problem. Thank you all so much in advance.

Mugen_1

My '97 behaves in a similar fashion. It's been recently Seafoamed, has new spark plugs, a new coolant temp sensor and new serpentine belt. When my engine is warm and I'm in "D," it hovers between 200-400 if nothing else is running, slightly higher with my headlights on, and "normally" with the A/C on. Mine has never stalled out, however.

A common suggestion here, and something I've yet to perform, is to clean the throttle body and idle passages.

There is also this:

https://www.clublexus.com/forums/ls4...d-problem.html

niteriyder

Might want to check Idle Control Valve if the car stalls out...easy to get to right in front of the engine.

Mugen_1

^ And a good ~$600-ish part if it needs replaced.

chuckhusty

Thanks guys. Tomorrow after I get off of work I will try and clean the ICV. I'll let you all know the results!

timmy0tool

iTrader: (7)

sounds like the shop could have touched something during the starter install. the intake mani does have to come off adding potential risk. they possibly have forgotten to put back a vacuum line perhaps? inspect their work first before ordering parts. a good cleaning is always helpful regardless.

LScowboyLS

This symptom is most commonly the Idle Air Control Valve, can also frequently be caused by leaking ECU caps

of course, as TimmyOTool stated, the first suspect would be a little boo-boo during the starter job, especially considering how invasive that job is.