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PT Cruiser Troubles

Hello, everyone. I have a 2007 PT Cruiser that’s just about to hit the 100,000 mile mark. My problem is when stopped, the car feels like it wants to stall, but only when the AC/Heater/Defrost is on. Also, when it starts to act up, the heater stops working, leaving only the fan to blow air around. It doesn’t happen all the time, but enough to make me turn off the heater or whatever I’m using when I come to a red light. It just started doing this and I just wanted to have a rough idea as to what it was before I took it to a mechanic. Thanks!

Stop by a parts store for a free battery check. If you have not had a new battery put in in the life of the car now may be the time.

If you have not had it done recently, have the Idle Air Control valve cleaned and/or diagnosed. It sounds like the engine is idling too slow and not compensating for the A/C load.

Hope this helps.

To piggyback Lili’s post, I have the same issue with my 2003 PT Cruiser (and my sister does with her Cruiser). The A/C or heat wants to kill the car when idled (this includes when I start the engine; often have to turn off the air before I try to start the car). If I move the car into Park, it’s fine. Reverse or Drive, it’ll die, so backing up is problematic, since I often don’t have to press on the gas to back up.

I have taken the car in to have this problem addressed at least twice, but the guys at the shop say that the best they figure is bad spark plugs/connection to the plugs. Though they cleaned them up and changed them twice, it’s not resolved.

When ant of those components are on, it puts more load on the engine. Esp the AC, but even turning the heater on increases the load on the water pump and-- if the heater fan is on – the alternator. I expect you have some minor problem. Maybe you simply need your idle speed adjusted to factory spec. Or you may have an air leak in the vacuum system. A malfunctioning PCV or EGR could cause this too. Those would usually throw codes, so you might want to get your codes read. And it could just need a tune-up is all. If this were my car I’d bring all the routine maintenance suggested by the owners manual up to date before throwing any serious money at this problem.

At 100,000 mi;es your throttle body could need cleaning also/

Sometimes a bad ground at the engine to body ground wire can make that happen. Remove the body end and scrape it. Clean battery posts. Of course, there could be more likely things wrong.