I have been trying to find out why my car hesitates when warm and have replaced alot of different things and even had the fuel injection and oil flush service (BG products) to no avail. Today I finally bought a multimeter and checked the front three injectors and one was at like 35 and the others at about 12. I replaced the injector and no more hesitation!! Awesome, I don't have to go buy a fourth gen now! My car still idles funny though and it makes a pinging noise but I think it might be the catalytic converter or part of the exhaust getting hot and tapping or pinging. I'll check that out for free probably at a muffler shop. I did learn to use the KISS theory from now on--Keep It Simple Stupid--because I did a whole bunch of reading and thought that tons of stuff was wrong when instead I finally just checked the basics and found most of my problem. BTW does anyone know the symptoms of a bad catalytic converter? I might have to spring for a racing one if it is bad, bummer.

 

Hi,

to tell of your catalytic converter gone bad by smelling rotten eggs at a curtain time,

 

It's your knock sensor. Go to Rat Shack and pick up a 470K ohm resistor and put it on your KS harness. That ought to give you about 10hp. It did for my car at least. Runs fine so far (put the resistor in about 10k ago).

 

10hp? noooo, actually it gives you none, you just can restore lost power, but not really. It only makes it seem like that because the ECU never detects pinging or knocking and doesnt switch to the maps designed for when a knock/ping is present.

Also I'm going to step up and say dont run it unless you are aware of the consequences. Blowing a motor is not cheap.

For the Cat thing, I would just unbolt it and check the honeycomb crap. Worst comes to worst, buy a test pipe from WSP, $35ish vs $100ish or whatever.

 

I've already replaced the knock sensor and harness but I may need to recheck it w/ my multimeter to see what's up. I had done the 470 resister thing in the past and the car did run much better and I also have the KS TSB harness on it. I need to experiment with just the regular harness alone and then with the resister in place. I think that the knock sensor might actually be doing it's job though because I know my motor pings like the exhaust pipe is too hot or something. I've never smelled the rotten egg smell from my car and I think I can get it checked out for free at a muffler shop. Does anyone else know why the engine may be pinging like this? It only happens when warm and pings for a few seconds after it is shut off too.

 

if you hear the pinging noise after the car is off thats just the metal contracting, if its the same sound when its on and doesnt really go with the engine then its probably just the metal expanding.

 

Yeah, I figured it wasn't what most people think of as engine "ping" like a combustion chamber ping. But doesn't that mean that something is getting really hot? I know motors get hot but I can't think of another one making that noise. Plus I think the knock sensor is going off still and I don't know if it has anything to do with that.

 

Hi,

when my engine is warm i can hear that sound in the car engine is running and when i turn of the engine i can still hear that sound, i think it is ok,

 

Thanks, a friend told me it might be another injector going bad and causing the car to run lean. He says that it might be causing the exhaust from that cylinder to be really hot and ping. I am going to check that in a few minutes after I figure out how to check the back three injectors. I will post when I find out what is wrong just in case it helps someone else.

 

Just to update, the other injectors are fine, I think, so it is still a mystery.