My 1998 Dodge Neon has been stalling after it is warmed up. It runs great when the engine is cold but once the temperature gauge gets to the middle it stalls no matter how fast or slow I’m going. Once it stalls it won’t start for about 10 to 15 minutes while the engine cools a little. Then it will start and run fine for a few more minutes until the gauge reaches the middle and it will stall again. I’ve had my cam sensor, crank sensor, and ignition coil replaced and the problem hasn’t been fixed. When I bring it to the garage they tell me that no problem codes are showing up and by the time they look at it, it has cooled down enough to run and they can’t see a problem. Any ideas? Thanks.
The parts you threw at it are for ignition. Are you sure it is losing spark, or just guessing? I ask because I assume some diagnostics has been done other than just reading for codes.
In order to run, an engine needs four things, air, fuel, compression, and spark. Stalling means a loss of one of these. Spark has many ODB monitors, so losing it usually leads to a code. Air has a couple, but many problems can cause stalling without a code, like dirty throttle bodies and IACs. If feathering the throttle during a stalling event has any effect, I’d suspect that.
Fuel only has codes based on injector feedback. Dirty injectors only leave a code when they cause lean condition misfires. The fuel pressure and pump are typically not monitored by ODB. These need to be checked with a fuel pressure gauge during a stalling event.
Compression should be easily checked once warmed up. A standard compression check can tell you if this engine is just flat worn out.
Other things to worry about are vacuum leaks. These should set a code, but there are times the leak can cause stalls before the lean burn monitor is tripped. On older cars like this, a dirty EGR that sticks open is a good candidate.
So if I’m to understand this correctly, the mechanic isn’t willing to spend enough time with your car to get it warmed up so it can be diagnosed so parts are simply being thrown at it ? Or is it intermittent ? From what I understand you to be saying, it isn’t. If this is correct you may want to find a mechanic willing to take the time to properly diagnose. One thing I would try if I was diagnosing this and the above parts had already been thrown at it would be to let it cool down. make sure it’ll start then turn it back off. I would take a blow dryer and heat up the PCM. Once it’s warmed up I would try to start it. If it wont start, the problem has now been found.