My friends Monte Z34 is struggling. The car has 85,000 miles on it. The car was running terrible. The shop said the computer was detecting a 3rd cylinder misfire, so they replaced all the spark plugs. It did alright, but now it is doing it again. The rpm's are erratic, they will hang a bit, drop, and then take off. The SES light is flashing every once in a while, the manual says that is a misfire detection. So, is it the misfire again?? If so, why??? Is it fuel related??? Sensor realated??? (o2...) It hesitates and sputters, but not all the time.

Problem #2 - Sometimes the LOW TRAC light comes on and the ABS kicks in under light braking..... it that a sensor??? why would it do that?? I have never worked with ABS so I dont know how to diagnose......

Please help me out here......she has come to me for help, and I dont know much about this car. Thanks a lot, any suggestions are helpful...

 

it's obdII, if you didn't already know that. you need to scan it, find the code and trouble shoot. i don't know much about abs either but i'd suspect a senser, and if you're scanning it i bet you can scan the abs too. you should make sure the tune up's good and all the filters are clean, but you knew that already too i bet.

 

I would pull that plug and take a look at it again. If it fouled again there may be more serious issues at hand. A good mechanic would have looked further into the problem of a single cylinder misfire. It could be as simple as a bad plug wire. At 85k they should have replaced them as well as part of a proper tune up. As far as the ABS, many problems can be traced to intermittent wheel sensors. Unless you have an OBD II scanner it's best left to the professionals. ABS components are pretty pricey. I would however go back to the shop who did the tune-up and question them as to why it is running bad again. He may not fix it for free, but you may at least get a diagnosis on his nickle.

 

what is obdII??? As far as i know, the filters are clean and the plug wires are new too. I will see if a friend of mine can get a scantool from where he works..... any more ideas???

 

OBDII means on board diagnostics, version 2. It was an attempt by the federal goverment and auto manufacturers to standardize data connectors for access to a vehicle's on board computer and to also standardize trouble codes. The real beauty of OBDII is that the trouble codes are more specific as to where a problem lies. Older trouble codes may have only had one or two codes for a specific sensor, now they have many. It allows the technician to have more info to make a better diagnosis and to help the consumer so as not to have to buy parts he doesn't need. If it's doing the same thing as before the plugs were replaced I would pull #3 plug and take a look, that's the only way to see what's going on. Chances are it is fouled. As to why if that's it-possibly a leaky intake gasket or something worse. If you can get a scan tool that's the place to start.