Here for advice.

I picked up a cheap 1988 Oldsmobile Intrigue GL. It has a 3800 motor in it. The guy told me it stalled sometimes when coming to a stop and he knew it threw a MAP sensor code so he changed it (with one from a scrap yard so that could have been bad too) and he suspected - from online research - that it needed a new crankshaft position sensor.

He followed me home and I had to pull over several times while he got it restarted, but it made it.

The next day I drove it and couldn't get it to stall. The only things I did was top up the oil (1qt low), did some mild degreasing of the motor, and clear the P0107 code. It drove fine! For a day.

Next day, I made it home after going through what he did (stalling nearly every stop sign).

Next day (yesterday)... I can't get it to start. It cranks and the battery is fine. One odd thing is the speedo flips up to 100mph briefly while cranking.

I'm trying to decide if I should bother working through this. I bought the car for the express purpose of scrapping it in 6 months to take advantage of a government incentive if my area. So I do NOT want to put much money into this! But I was expecting to DRIVE it to the scrap yard, and it would be NICE - since I'm paying for insurance for 6 months @ $450 (requirement of the program) - if I could use it once in awhile for errands. But since it won't even start at this point, maybe just paying $100 for the tow is the way to go. I can get an off-brand MAP sensor for $20 and an off-brand CSP sensor for $10 to $15, so parts are cheap... but that'* only if that solves the problem. At this point, I'm not convinced.

Thoughts? Advise?

Thanks.

When it won't start, have you checked the basics like spark, fuel pressure and injector pulse?

Wow, I should be ashamed of myself with that late night inaccurate description.

I'm no mechanic, but I shouldn't have posted like an idiot. I said, "I can't get it to start", but that'* not true. I meant it won't stay running. It does start. Sometimes for a second and then dying, sometimes for several seconds but with the tach jumping all over the place (the engine doesn't sound like the tach is suggesting) before dying, and once in awhile it'll run seemingly fine for 2 to 10 seconds before suddenly dying. Its that latter event that seems to throw the P0107 code. I suspect the other quicker runs don't allow time for the code to generate.

My guess is that both the MAP and crankshaft position sensors have failed. Its the weird speedo jumping thing that has me wondering if I also have another gremlin. I'm willing to chase down the two sensors but if people here (presumably with worlds more experience than I have) feel that I'm still likely to be in trouble even after fixing those two things... then I'll probably just quit before I'm too far behind.

As I said, I'm not a mechanic. I'm reasonably handy and I have basic tools. I've done things like re-and-re brakes, suspension, CV joint. I've never rebuilt an engine or diagnosed anything that wasn't clearly spelled out on OBD. I'm not saying I am in over my head, but that'* why I'm here, really, to see if I am

That code could be set by the hard starting problem.....

Let'* eliminate fuel....spray carb cleaner into the intake, while someone cranks the vehicle....if it runs as long as you spray, and then dies when you stop, it'* a fuel delivery problem, either f/p pressure or injector problem.....

One question, is the MAF sensor located in the snorkel or is it in the throttle body on this year?

Alright, I was at the autoparts store when I saw your post come in, so I bought a can of carb cleaner. It was on sale... bonus

We tried two times where it wouldn't start (or, rather, stalled very shortly after starting). On the 3rd attempt it ran normally for about 8 seconds, about 3 or 4 of which I was spraying the cleaner. "Normal" except that during that time I was spraying, the engine sounded like it was revving higher and higher, which stopped shortly after I stopped spraying. A few seconds later it died. We repeated again a few times without spraying and on the 5th or 6th try we got a "good start" and it ran for about 4 minutes. I then shut it off. I haven't been able to get it to run since, with or without the cleaner.

This intermittent nature really sucks.

As for the MAF sensor... photo coming up

I think I have this right, after consulting some diagrams.




Location of MAP and MAF sensors on 1998 Oldsmobile Intrigue

Try starting the vehicle with the MAF, not the MAP, disconnected....

If the car does not start, and then you disconnect the MAF and it starts, buy a spray cleaner specifically for the MAF, and remove the sensor, and clean the sensing element.....put back in car and see if it runs ok.....if it doesn't you may need a new sensor....

Thanks.

OK, I tried starting (nothing disconnected) and doesn't start (although, thanks to intermittency, who knows). Disconnected MAF and no change.

I repeated a few times with and without MAF and sometimes it starts in either case but quickly died.

I realize this doesn't rule out the MAF, but it doesn't confirm it, right?

At this point I haven't bought the MAF cleaner because if I understood your post I should have only done that if it did start (consistently) with the MAF removed. Although I'm sure it wouldn't hurt to clean it out anyway.

Remove the O2 sensor(one between ex manifold and cat).....disconnect MAF.....attempt to start car.....if it starts, could be plugged exhaust....

If it still doesn't start, spray carb cleaner into intake....

If it still doesn't start, then check for spark and if ok, check compression....

I'm curious why you're not at all looking at the two things that seem the most obvious? The car is reporting a MAP sensor problem and googling the symptoms (jumping tach and stalling frequently) revealed tons of advice on replacing the crankshaft position sensor. You don't think either/both are worth investigating? Or you're working your way there?

I'll try the O2 removal tomorrow.

I checked spark when you first mentioned it. Good spark on all plugs. I'm not sure how to check compression, but...

Keep in mind that when it runs, it runs fine... if only for a few seconds (but sometimes minutes). If there was a compression problem or plugged exhaust, wouldn't that be less intermittent? Consider that I made one trip for several miles and never had a problem (until I parked it and then had problems ever since).

I've ordered the MAP and CP sensors because I was ordering other stuff from Amazon anyway.