Caminiti

I installed a brand new delphi opti about 6 months ago. I've put maybe 5k miles on the car since then. The other day the check engine light comes on and its a DTC 36 hi res failure. Tonight I am driving home and I notice both the tach and speedo are twitching. I stop at a gas station for a few and when I go to start the car it was hard to start. I had to give it gas, but once running I drove for about 1.5 hours home and it ran and idled fine. The tach and speedo would still jump around, but I couldn't hear the engine actually changing speeds. Is there anyway to test to see if its really the opti or maybe something simpler like the opti harness? Thanks.

600hplt1sm

Yes, you can unplug the opti harness up on the passenger side of the intake. With the ignition on using a volt meter measure the voltage on terminal b. on the pcm side. If it is between 4 to 6 volts turn the key off and reconnect the harness. Then unplug the harness from the opti turn the key on and check terminal B on the plug that goes into the opti. If it is between 4 to 6 volts then I would say the harness is OK. Although check for Blue/grennish corrosion anyway. If those readings are correct the shop manual says that its either a faulty distributor connection or faulty distributor. I just had the same thing happen to me but mine was the low res. This test is from a 95 Shop manual. You should give yourself a sig with at least some basic info about your car. It makes it alot easier to help you

Here is a link to show you a diagram

http://shbox.com/1/95_ign_system_schematic.jpg

Caminiti

thanks, I will test that here in a bit.