1986 Olds 88 won't start

[bill buttermore]

Working on a friend's car, and need some help. 1986 Olds 88 3.8 liter VIN 3 engine 70,000 miles. New plugs and wires about 3,000 miles ago. At that time we also pulled to fuel rail to check for a leaking or bad injector - all were functioning normally. But it had a weak fuel pump ~24 psi, that finally gave out Sunday. Car wouldn't start, no fuel pressure at rail. Replaced pump, car still won't start. 38 psi of fuel on rail with ignition on - 40 psi while cranking. Pulled plugs - wet with gas. Dried plugs out and confirmed spark at all six cylinders. Not the strongest spark, but was checking in daylight and seemed like enough to make her go. Engine does not seem to fire when cranking. Tried again to start and pulled plugs again - #1 plug really wet with gasoline, #3, and #5 dry. #2 a little wet, #4 and #6 dry. No check engine light. No codes stored. Dried and replaced plugs -held accelerator to floor in attempt to clear flooding condition while cranking - car would not start. Following that attempt, #1 wet again. At end of extended crank, it almost sounds like it has jumped time, but at only 70,000 miles?

It seems like it is not providing spark at the correct time, or maybe only providing fuel to #1. I wondered if maybe a bad cam sensor or ICM? I plan to check the signal to the injectors with 194 bulbs next. Any ideas?

[Mechanical Mike]

Disclaimer - I'm not familiar with VIN 3, the following info is based more on VIN C & later years.

The engine should run without the cam sensor so you can try unplugging it. You can also try unplugging the MAF. I'd pull the coils & ICM & see if any of the green goo looks like it melted. The ICM grounds through the mounting bracket so clean the top of the mounting bracket, both sides of the mounting plate and the bottom of the ICM. I smear a little dielectric grease on all four surfaces to slow down future corrosion. We don't want you to have to clean it again in another 24 years.

A compression test should show whether or not it jumped timing.

[bill buttermore]

Thanks, Mike. I'll take a look at that stuff in the morning and let you know.

[Archon]

Those engines are known for jumping timing when the plastic on the gears turn brittle and break off. I worked on an '87 that did that. Pulling off the intake tube, you could hear it, and confirmed it with the old thumb over the spark plug hole.

Edit - I'm not sure of the mileage at the time, but know that it was under 100K.

[bill buttermore]

Thank you Mike, thank you Dick, and thanks to my wife Judy who said "Could it have jumped time?" I replied: "with only 70,000 miles - not likely." Well, it sure did. After I checked the injector harness (all lit up); the coils primary and secondary windings; (all read good: 1.0 Ohm and 5.99-6.02 kOhm); the ICM grounds and connector (all clean); the compression test revealed what a thumb would have shown a lot more quickly. Now all I have to do is tear off the front of the engine and replace the timing set. $25 for the gear set and $13 for the gaskets. Piece o' cake. I am a happy boy.

The answer often seems easy and obvious when you know what it is. Before you know the answer, things are not so clear. Thanks again, guys.

[Archon]

Have fun, Bill. While you're in there, you may want to replace the chain tensioner, too. If you have my luck, the harmonic balancer will go belly up when you pull it. Took forever to find that problem. Even seasoned mechanics didn't diagnose it properly.

[bill buttermore]

Thanks for the "head's up" Dick.

[Jrs3800]

How do you like the replacement gear set? Nothing like all metal... Been there and done that... They jumped time anywhere from 50kto 120k... it was common place for them until they got away from the nylon aluminum timing gear...

[bill buttermore]

Yeah, Don, the replacement set was all steel, for sure. There were bits of nylon and aluminum everywhere. Dropped the pan to clean out all the debris. Got a new tensioner (the old one was in pieces) and a new cam button (thrust bearing). All that was left of the old cam button was the spring. Had to make a little flat spot for the new button to ride on the old cover. Autozone was the only store locally, well, 30 miles away, that had the cam button available. Judy was up for a dinner in Des Moines that night, so all worked out okay.

And, Dick, I think I may have lucked out with the HB, I had to jam the flex plate and use my 4-foot cheater with the jackstand to pop that bad-boy crank bolt. But, once the bolt was free, the HB slid right off the crank.

[Archon]

I'm glad to hear that you have better luck than I, Bill.