General: 850: 850 cutting out on motorways

[damo850]

Not sure whether it's 10 or 20. I retrieved the flashcode by using the "A" diagnostic unit in the engine compartment with the function selector cable in socket 6.

[Andrew Parreira]

Originally Posted by damo850

Not sure whether it's 10 or 20. I retrieved the flashcode by using the "A" diagnostic unit in the engine compartment with the function selector cable in socket 6.

See what comes out of socket 2
A 20v will say so on the rocker cover (plastic thingy covering sparkplugs)
10v says DOHC, i think.

Andrew

Edit: also have you removed the 3-1-4 code, if not do so and see if it comes back next time you conk out.

[Luxobarge]

Originally Posted by damo850

Sorry, my mistake. I've already replaced the camshaft position sensor, I just wrote "crankshaft" in the original post. Any other ideas?

Then I'd change the crankshaft sensor. When this fails you will get no spark and no fuel. It sounds like it's failing when hot.

[damo850]

Interesting: it's a 20 valve, but I just checked the code using socket 2 and I got a 1-2-1 error (previously I'd only had 1-1-1). Yes, I've reset the socket 6 code in the past and 3-1-4 is the latest code. Prior to replacing the camshaft position sensor I was getting a 3-2-4 code...

[Andrew Parreira]

Originally Posted by damo850

Interesting: it's a 20 valve, but I just checked the code using socket 2 and I got a 1-2-1 error (previously I'd only had 1-1-1). Yes, I've reset the socket 6 code in the past and 3-1-4 is the latest code. Prior to replacing the camshaft position sensor I was getting a 3-2-4 code...

May i suggest a new sensor may be in order, if the code has re-appeared since you replaced it the replacement may be faulty?

Failure of the MAF would not cut the spark, it would make the car run crap.
The MAF is a common code as often people disconnect the MAF while working on the car then start it to test their work without first connecting the plug.

Andrew

[damo850]

Thanks Andrew! I think what I'll do is reset all the codes, check the MAF, try a new sensor and see what happens Fingers crossed and will let you know how it goes.

[TurboZutek]

Here's a rough and ready way to test sensors:

Get the engine running and then take a small hammer and tap the sensor a few times (gently) - watch for the engine stalling out.

Or

When the car has failed, get some compressed air spray and turn it upside down and coat the sensor with the frost that will fly out. This will cool the sensor and likely make it want to work again. If the car magically starts and runs it's very likely the sensor you just cooled off is the problem.

This simple approach can save a bunch of cocking around swapping this and that.

Chris...

[Chris_Rogers]

Originally Posted by Luxobarge

Then I'd change the crankshaft sensor. When this fails you will get no spark and no fuel. It sounds like it's failing when hot.

I'd tend to agree, there does not seem to be a fault code for the crankshaft (RPM) sensor on the Jetronic 3.2 system fitted to this car so I suspect it will show a cam sensor DTC for a fault with either sensor.

[damo850]

Well it turned out to be the camshaft position sensor in the end!

Basically what I figured out was that my mechanic originally diagnosed the camshaft sensor to be the problem, however he delegated the work to someone else who actually replaced the crankshaft position sensor Since my knowledge of car engines is quite limited, I thought the names camshaft and crankshaft were different names for the same part, so I didn't notice when I got the car back...

So the good news is that the problem is now solved, and hopefully this information can help someone else in the future without too much expense

[Luxobarge]

Originally Posted by damo850

Well it turned out to be the camshaft position sensor in the end!

I refer the honourable member to post #3.......