Aargh, car won't tell me what's wrong...

[ChrisV]

I'm used to that from old British and Italian stuff, but an OBD-II car usually tells you exactly what's wrong.

Got that $375 2001 Cavalier w/2.2 OHV engine (I know, that's what's wrong, right there...but I digress) for a friend. PO said it wouldn't start. Well, made sure it had a good battery charge and tried to crank it over. Cranks over fine. So I put the OBD connector on, first time didn't have it quite seated and it said it couldn't connect. Pushed the connector all the way on and got a connection but it said no codes.

Well, I was going to do a "tune up" anyhow, so I changed the spark plugs, and while I had them out, checked compression. Seemed ok. When cranking there didn't seem to be any noises like broken timing chain or pistons eating valves... Put the plugs in, and before connecting all of them, I put a plug in a wire and laid it on the valve cover to check spark. Had spark. Hmm.

When turning the key on, you can hear the fuel pump fire up for a couple seconds like normal. Checked the fuel pressure regulator, and there's fuel at the rail. Put some starting fluid in it and fired it up. Ran good and smooth for about 10 seconds, til it ran out of fluid. So obviously the crank position sensor is working and the cam position sensor is working. Which I'd figure considering it didn't throw codes for them. And it runs smoothly so the ignition is doing it's job, and the timing seems fine. it'll fire up every time on the starting fluid. And while it's running, there's no check engine light (though it does light up when it's cranking, so the bulb works)

I guess I need to check fuel pressure next. I was thinking fuel filter, but usually if it's getting by the filter enough to get to the rail, it'll run relatively good at idle, but not be able to rev (at least in every other EFI car I've had). I don't have a fuel pressure tester adapter that I can hook up to the car, though. Drat.

I don't want to just start throwing parts at it. I love OBD-II, but not when it's telling me all's well, when it's obviously not. Time for a Scotch. I think the Aberfeldy 21 year ought to do it...

[Rupert]

Out of gas?

[Eye of the Tiger]

plug the cam sensor back in

[ChrisV]

Out of gas?

Hardehar har! No, it's got a quarter tank AND fuel at the fuel rail.

[ChrisV]

plug the cam sensor back in

It is. First thing I thought of. Double checked it AND replaced it and double checked again. No codes and it's in there tight. Would throw a P0341. I'd say it was the crank sensor, but that controls the ignition, and it runs just fine when starter fluid is in it. Maybe the replacement cam sensor is bad, too, though supposedly the PCM will go into "limp-home mode" if it can't get a proper signal from the cam position sensor (and also throw the code to say, "hey, WTF, mate!")

[Eye of the Tiger]

pcm is fried

[ChrisV]

Hope not. It'll double the cost of the car... hahahaha! PCMs hardly ever go bad in one tiny specific area, however. But that's next on my list to have tested after fuel pressure. I'll have to take it to the dealer, though, for the Tech II to connect up. That's a tool I don't have and can't afford to buy.

[Eye of the Tiger]

anti-theft?

[ChrisV]

Would think that that wouldn't allow it to run even on starter fluid. Or even crank. But it's a possibility.

[S204STi]

You need to determine how much fuel pressure you have at the rail.  Just having fuel there doesn't mean much.  Many cars won't run or will barely run if the pressure isn't within a specific range, probably around 55psi for that one.  I'm not sure about that part though.

Oh, BTW; what does the security telltale in the dash do?

[JWC]

Check the fuel pressure before throwing anything else at it.   When you checked the rail valve, did it spray a foot or more into the air, or just a few inches? 

The engine has to run long enough for the OBDII to record a fault...or the fault has to occur long enough before the failure for a code to be present.  If you're not seeing a code, chances are a TECH-II will not either.

[ChrisV]

Like I said, I have to get an adapter to check the pressure. On my CIS mechanical injection cars, the pressure opened the injectors, so with low pressure they wouldn't open, but on my EFI cars that have had low pressure, they'd still open, just not run good enough to rev. The fuel pump runs like it's supposed to, audibly, and I've changed pressure regulators. But you're right, it doesn't seem to be getting enough pressure. When it stops raining I'm going to go back out there and pull the fuel line off and see how far it sprays (since I don't have an adapter for the pressure gauge, I figure if it hits the side of the garage, it's got more than a couple psi.. ). I was going to change the fuel filter as part of the tune-up anyhow, so I'll do that to rule out a clog there.

Once it's running, there are no lights on the dash. All of them light up when you turn the key on, however.

I had a similar thing happen on the BMW not long after I bought it. One morning it wouldn't start. But in plugging in, there was a code for the cam position sensor, which I replaced and it's been fine for the last 3 years. Which is why I was hoping there would be SOME sort of OBD code to go on.

I'm just hoping that it's not the actual fuel pump, as that's almost as much as I paid for the car... But I want to make sure it's right for our friend that we're giving the car to.

[Eye of the Tiger]

Friends don't give friends Cavaliers.

[ChrisV]

Friends don't give friends Cavaliers.

It's still better than what they had before (that was repossessed when they lost their job). But yeah... hahaha.

[S204STi]

Sometimes it's nice just to have transportation.  And really, they can be pretty dependable cars.

[Rupert]

Hardehar har! No, it's got a quarter tank AND fuel at the fuel rail.

Bad gas?

[ChrisV]

Ok, did the anti-theft check of the factory Passlock system. Supposedly it'll let the car start then die by shitting off the injectors. If you leave the key in the ON postion for 10 minutes, it resets and relearns. No dice. The anti theft light came on when you turn the key on initially, with the rest of the dash lights, but goes out almost immediately with the other lights that normally go back off. Still won't start and no anti theft light lit or flashing afterward. Put more fuel in it to make sure.

Off to get a fuel pressure tester. I'm sure it's really something simple...

[ChrisV]

No pressure testers available, but it doesn't matter, as with a new fuel filter in it, it starts up and runs just fine. Took it around the block to make sure, and it drives quite well. The old filter would let it dribble into the fuel rail. with the new one in, the pump cleared it's throat a couple times then there was a rush of fuel up to the front.

yay!

[JWC]

Good.

I've been amazed over the years by how many people turn cars loose because they "assume" more is wrong than it is.  That's why I suggested not to throw anything else at it until the pressure test.  A lot of cars get hundreds of dollars of parts thrown at them on assumptions, then sold and repaired for $50.

[ChrisV]

Yup. Total repair costs are now at $60. On a car that was bought for $375 that could be sold after a quick detail for around $2500-3000.

[Eye of the Tiger]

Good, now you can sell it to some suckers and use the money to buy a car for your friends! 

[S204STi]

GJ Chris.

[Rupert]

Can you fly over to Boise? I have a project for you...

[AutobahnSHO]

Nice going- amazing what kind of $$$ a little car skills will save.

A friend with a 2002-ish Toyota Sienna had the transmission conk out. They don't want to get a new one, period. They're moving to NY in one month. Van bluebooks around $4500.

Options at the Dealership were 
1- $4200 (installed) for a rebuilt transmission with a year Guarantee. OR
2- $3300 (installed) for a used transmission with one year Local Only guarantee.

I said check AAMCO, where they are getting $3500 for a rebuilt transmission with a national 3-yr guarantee...