1988 98 Regency 3800 no spark

[silicon212]

Hello there. Last night my Caprice threw its transmission, so back-up car time. Well, the back up car is a 1988 Olds 98 Regency, with the 3800 engine in it. Last night it ran great, parked it for the night, went out to start it this morning and no start. No spark. I checked the 3 computer fuses on the passenger side as well as all other fuses. All checks good. Anyone have any ideas, on what might be wrong with it? The most common things?

[maxwedge]

Originally Posted by silicon212

Hello there. Last night my Caprice threw its transmission, so back-up car time. Well, the back up car is a 1988 Olds 98 Regency, with the 3800 engine in it. Last night it ran great, parked it for the night, went out to start it this morning and no start. No spark. I checked the 3 computer fuses on the passenger side as well as all other fuses. All checks good. Anyone have any ideas, on what might be wrong with it? The most common things?

Crank sensor or wiring is number one, ign module # 2, should be scanned to see if there is an rpm signal reaching the pcm/ign module to confirm this possibility.

[silicon212]

Originally Posted by maxwedge

Crank sensor or wiring is number one, ign module # 2, should be scanned to see if there is an rpm signal reaching the pcm/ign module to confirm this possibility.

Thanks, I'll give it a shot. I was thinking possibly crank sensor too - it's a little oily down there. One more thing - the module is the plate the coils bolt to, right? When it comes to the Small Block Chevy, I'm pretty much the master, but this stuff I don't have a lot of experience with. Thanks!

[Master01]

Ignition coil is bad, I am 99% sure that is the problem.

[silicon212]

Originally Posted by Master01

Ignition coil is bad, I am 99% sure that is the problem.

This has 3 individual coil packs. If one was failed, the engine would run but very roughly.

There's no spark on any plug.

[Alibi]

No spark to any plug...I have to agree that it sounds like a bad crank sensor. Are you getting any trouble codes? If not, then yet another indication of the crank sensor since it usually doesn't trip a code.

Another possibility: corroded battery terminals... But I still lean towards the crank sensor.

[silicon212]

Originally Posted by Alibi

No spark to any plug...I have to agree that it sounds like a bad crank sensor. Are you getting any trouble codes? If not, then yet another indication of the crank sensor since it usually doesn't trip a code.

Another possibility: corroded battery terminals... But I still lean towards the crank sensor.

Yup .. no trouble codes at all. First thing I checked actually.

[Alibi]

No codes? In that case then the Crank sensor is prolly the culprit. $30, you have to remove the harmonic balancer (big PITA, just do a forum search) and then remove the old one and install the new one. Be sure that when the HB is back on that is spins freely and doesn't hit the tines on crank sensor.

The only other thing I could think of to check would be a bad ICM, but I believe you would still get spark--it would just be erratic and flakey, especially at operating temps.

[silicon212]

OK, I got it going. It was both the crank position sensor, AND ignition control module. An update - on a quick look it looked like 3 individual coil packs, but alas it was only one pack with 6 towers. I replaced it as well, for good measure. I also found an intermittent short in the wire (chaffed insulation) going from the module to the CPS - I'm sure this is what led to the death of the module. Fixed it with silicone.
The car now runs good and that's what I was after, of course.

The harmonic balancer wasn't too bad - then again I've done work in tighter quarters with less tools ...

[Alibi]

It is great to hear that we found the problem

The crank sensor, coils and ICM going south are among the most common problems with these engines.... I have personally replaced three sets of coils/ICM's on 3 different cars (mine, my brothers, my other brother's girlfriend's).