OMP Testing Question
#1
OMP Testing Question
Today I was helping a friend with his (new to him) FD.
It's throwing a code 27 (OMP) and tossing into limp mode whenever he gets on the throttle or up in RPMs.
I tested everything per the FSM and found only one thing out of spec, but that's if I'm reading the test correctly. Per the FSM, one of the terminals at the OMP connector (J, IIRC) should vary in voltage from 1.1v to 4.2v under acceleration. Parked, his stays exactly at .9v even when he revs the engine.
Is that sufficient proof that we need to change the OMP, or must we take it out for a drive and test that terminal under load as well?
Dave
It's throwing a code 27 (OMP) and tossing into limp mode whenever he gets on the throttle or up in RPMs.
I tested everything per the FSM and found only one thing out of spec, but that's if I'm reading the test correctly. Per the FSM, one of the terminals at the OMP connector (J, IIRC) should vary in voltage from 1.1v to 4.2v under acceleration. Parked, his stays exactly at .9v even when he revs the engine.
Is that sufficient proof that we need to change the OMP, or must we take it out for a drive and test that terminal under load as well?
Dave
#4
Urban Combat Vet
iTrader: (16)
IIRC, the OMP is strickly rpm based, so testing under load isn't likely to change things. But it's a PITA job to change them out, so if you have something that will show peak voltage it couldn't hurt.
FWIW, my car ate two OMPs. I have no proof, but a strong suspicion that the stock ECU was cooking the OMP sensor at WOT...which is where I saw the on-set of both CELs and subsequent limp modes. While it doesn't specify, I think code 27 does relate to the sensor. If you could figure out a way to check, or maybe someone else can confirm that before having to change a second one......?
I also made a short how-to thread a while back on changing out the OMP in the car that might be some help to your friend.
FWIW, my car ate two OMPs. I have no proof, but a strong suspicion that the stock ECU was cooking the OMP sensor at WOT...which is where I saw the on-set of both CELs and subsequent limp modes. While it doesn't specify, I think code 27 does relate to the sensor. If you could figure out a way to check, or maybe someone else can confirm that before having to change a second one......?
I also made a short how-to thread a while back on changing out the OMP in the car that might be some help to your friend.
Last edited by Sgtblue; 12-15-08 at 09:11 AM.
#6
Urban Combat Vet
iTrader: (16)
If you have to pull the turbos, that'll help alot as far as access. Be sure to get new copper washers and the 'O' ring from Ray.
Edit: In my first post I suggested checking peak voltage under load if you could...but of course you can't in limp. duh.
Edit: In my first post I suggested checking peak voltage under load if you could...but of course you can't in limp. duh.
Last edited by Sgtblue; 12-15-08 at 01:10 PM.
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