AndyS
NAXJA Forum User
- Location
- Shrewsbury, MA
Can anyone point me to where I can find specifications for testing the engine electrical components, like TPS, MAP sensor, etc? My Haynes manual doesn't have these listed...
My '94 4.0 with 170K miles failed emissions and the local dealer doesn't even want to take the time to look at it. I have the usual new O2 sensor, new plugs/wires/cap/rotor, as well as a new catalytic converter, but my NOx is still high (5.2 - passing is 3.0). CO and HC are great - passed those with flying colors.
The shop that replaced the converted said that both the old and the new one weren't getting very hot - around 350 degrees F with an IR thermometer, and 600-700 is minimum to have the cat fire correctly, no? Additionally, my engine temp never seems to get over 150-160 F. I've replaced my thermostat TWICE now, just to make sure it's working, and I even tested one of the old ones in a pot of water on the stove, and it worked fine...
Anyways, I'm assuming that it has to be one of the peripheral components giving the ECU a bogus signal, so if I could find out what values these items should test at, I can start eliminating things.
Thanks for the help -
My '94 4.0 with 170K miles failed emissions and the local dealer doesn't even want to take the time to look at it. I have the usual new O2 sensor, new plugs/wires/cap/rotor, as well as a new catalytic converter, but my NOx is still high (5.2 - passing is 3.0). CO and HC are great - passed those with flying colors.
The shop that replaced the converted said that both the old and the new one weren't getting very hot - around 350 degrees F with an IR thermometer, and 600-700 is minimum to have the cat fire correctly, no? Additionally, my engine temp never seems to get over 150-160 F. I've replaced my thermostat TWICE now, just to make sure it's working, and I even tested one of the old ones in a pot of water on the stove, and it worked fine...
Anyways, I'm assuming that it has to be one of the peripheral components giving the ECU a bogus signal, so if I could find out what values these items should test at, I can start eliminating things.
Thanks for the help -