1995 No tach signal and won't stay running?
#1
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From: VA Beach
1995 No tach signal and won't stay running?
Picked up a 70K 1995 5spd car. BONE STOCK. Wont stay running. When ya turn key it starts right up than dies a second later. Will continue to run in either. Dash displays no tach signal at all.
Replaced fuel pump (did not think it was issue but I had one) and verified pressure. Replaced CAS and Coil pack.
From my searching I read the 94-95 tach signal was sent from the coil pack to dash and ECU and if ECU does not see tach signal on startup it shuts down fuel injectors. Sounds like my issue. Now how do I verify and fix it?
It is a 4 pin coil configuration.
Thx!
Replaced fuel pump (did not think it was issue but I had one) and verified pressure. Replaced CAS and Coil pack.
From my searching I read the 94-95 tach signal was sent from the coil pack to dash and ECU and if ECU does not see tach signal on startup it shuts down fuel injectors. Sounds like my issue. Now how do I verify and fix it?
It is a 4 pin coil configuration.
Thx!
#7
test ign- to ground and see if it's faulted to ground. it shouldn't be -- if youre in diode test mode (beeps), then you should hear it rapidly pulse like that when running/cranking. if its solid ground that's an issue (maybe issue in the tach itself?)
but you said you replaced the coilpack, so that should have fixed the no tach issue.
but you said you replaced the coilpack, so that should have fixed the no tach issue.
#9
Also check the crossover tube for cracks. I had a similar issue and the fix was just a new crossover tube, it would start up just fine, the die right after,I could keep it alive if I kept giving it throttle. My crossover tube had a hole in it on the underside of it, and since it was after the MAF it treated it as un-metered air. Sometimes the most annoying issues are the simplest! Good luck.
#12
Thread Starter
Elite Member
iTrader: (11)
Joined: Apr 2007
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From: VA Beach
So I now have swped in two known good 94 coil packs and a known good ECM.
Still same thing. Starts like normal and 2 seconds later ECU cuts off injector pulse.
I read somewhere that in 94 95 if ECU does not see tach signal it pulls injectors to shut down motor.
Is there a way to test tach signal at the ECU?
How
What wire off coil pack could I jumper to ECU to see if the wire broken somewhere?
I know this 3/95 build used a 4 wire coil pack but Intresting enough the plugs that come into coils only have 3 wires in them..?