Tim Groth
SCCoA Member
Pretty well stumped on to where to start on this one.
Car in question is bone stock '89 5spd. It's my daily driver with 207K. Recently replaced Headgaskets at 204K - no driveability issues since or before they went out. Car has been a solid daily driver/beater for my commutes to and from work.
Recently the car has developed an intermitten problem, that doesn't happen regularly at all and it has me stumped. Its kind of like a surge. The car will rev up and then drop idle, rev up then drop idle...it typically will do this for a 15-45 second period of time and then its fine. Prior to doing this the car runs fine, drives fine...it has it's little spasm...then its back to normal. This has happened while the car is parked and also while driving...when it happens while driving I typically down shift and push through and again it clears up. The car will chug if at a low RPM - down shifting to a higher RPM you can feel the miss but nowhere as near intense as at lower RPMs. And when I say chug where talking first time 5 speed driver chug...its pretty intense.
I have checked the balancer - no wobble, bolt is present
Fuel pressure is good (haven't tested it during symptoms however) again so intermitten its hard to do so, for it happens randomly.
All connections to DIS,Cam,Crank sensors are tight and clean.
My thoughts on what it could be
DIS Module
Crank Sensor / Balancer
Key Switch
Also as a sidebar - the car since I have owned it has an electrical surge that can be seen in the headlights and interior lights...its a hint flicker and kind of lines up with this issue. when I did the HGs I replaced the main ground wire to the battery from the block for it was in horrible shape...didn't change the problem.
Any thoughts on where to look next would be great.
-Tim
Car in question is bone stock '89 5spd. It's my daily driver with 207K. Recently replaced Headgaskets at 204K - no driveability issues since or before they went out. Car has been a solid daily driver/beater for my commutes to and from work.
Recently the car has developed an intermitten problem, that doesn't happen regularly at all and it has me stumped. Its kind of like a surge. The car will rev up and then drop idle, rev up then drop idle...it typically will do this for a 15-45 second period of time and then its fine. Prior to doing this the car runs fine, drives fine...it has it's little spasm...then its back to normal. This has happened while the car is parked and also while driving...when it happens while driving I typically down shift and push through and again it clears up. The car will chug if at a low RPM - down shifting to a higher RPM you can feel the miss but nowhere as near intense as at lower RPMs. And when I say chug where talking first time 5 speed driver chug...its pretty intense.
I have checked the balancer - no wobble, bolt is present
Fuel pressure is good (haven't tested it during symptoms however) again so intermitten its hard to do so, for it happens randomly.
All connections to DIS,Cam,Crank sensors are tight and clean.
My thoughts on what it could be
DIS Module
Crank Sensor / Balancer
Key Switch
Also as a sidebar - the car since I have owned it has an electrical surge that can be seen in the headlights and interior lights...its a hint flicker and kind of lines up with this issue. when I did the HGs I replaced the main ground wire to the battery from the block for it was in horrible shape...didn't change the problem.
Any thoughts on where to look next would be great.
-Tim