Misfiring off and on

Slaybrhamlincoln · Post by **Slaybrhamlincoln** » 22 Dec 2016, 15:02

Hello I'm about to go crazy with this car lol it misfires really bad sometimes when I hit the gas it doesn't even move then it will clear up and go completely away. So far I have installed new plugs wires cap rotor coil. And have had it to several mechanics but it never seems to act up when I've taken it to get looked at lol. Does anyone have an idea what might be causing this problem?

Thank you!

Post by **Clemens** » 22 Dec 2016, 16:43

Turbo or NA? What year? Give us a chance to help.

If turbo, did you use volvo plugs? Non volvo plugs can cause issues on turbo engines. Cap and rotor: bosch or something else?

Is the car running ridiculously rich? This could cause these symptoms. Have you replaced the temperature sensor next to the thermostat lately? If this one is bad your motor will run really rich.

Post by **sleddriver** » 23 Dec 2016, 13:38

Given the age (1998), I'd check the insulation on both the camshaft & crankshaft position sensors. It's likely rotted off by now and possibly shorting on occasion. When this happens the ECU will lose it's mind, forget what degree the engine is at and be unable to correctly fire the plugs & injectors. Result? It'll run really poor and misfire. Both wiring harnesses are on the distributor side towards the firewall.