Pavlo

Has anyone had a failed cam and/or crank sensor on an early car?

If so what were the symptoms?

Would you say it's worse as the engine gets hotter?

i am trying to diagnose a problemus-gremlinus which results in #3 injector not firing despite what looks like a perfect loom connection.

Paul

T-gro

I had a failed cam sensor on a UK 94 car.

The car would cut out, then refuse to start for a while.

It's hard to say regarding temperature, but I'd guess it was an issue. It was at it's worst in heavy traffic, when I'd imagine the heat was allowed to build up.

It only happened in those circumstances too, it never happened while moving, although it stalled while exiting a multi story once. It caught me unawares, the power steering stopped working (of course), and unable to steer quickly enough I mounted a kerb and nearly ran an attendant over

It started straight away then though.

Delboy2

Just a thought, the injector coil isn't breaking down when subjected to heat for a period of time?

Cheers

Pavlo

I don't think so, injector fires perfectly when driven direct, resistance checks out too.

I am looking at loom weirdness or intermitent sensors I think

Nathan L

I had a cam pos sensor fail on an 01 WRX.

It was fine all the time the car was cold but when warmed up it was a pain in the ****.

It caused a miss type sensation between 3-4k revs as the turbo woke up and if you tried to go over 6k revs the car would judder very badly.

Nathan..

Pavlo

Although the MY01 is slightly different to the 96, it would appear it is possible for the car to run in some fashion depending on the type of failure.

I will know more tomorrow.

Paul

snowcrash

dave11980 on scoobyzone had a failed cam sensor on his classic wrx (96 i think)...

http://www.scoobyzone.co.uk/viewtopic.php?t=3433

Delboy2

Does No3 injector fire(trigger) when directly wired from ECU?
Is there a possibility that the output driver on the ECU is faulty on that particular channel?

Cheers

Pavlo

tried another ECU and it don't work

can someone past some text from that scoobyzone thread, my web(non)sense at work filters it out as "games"

Paul

P20SPD

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Dave11980

Scooby Nutter



Joined: 19 Jan 2003
Total posts: 683
Location: Bristol
Age: 23
Gender: Male Posted: Thu 04 Dec 2003, 17:52 Post subject: Misfire or something else?

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Just had my car back after the most expensive service ever. Had to have my coils chaneged because of a misfire problem.
The car seemed fine the other day, but seems to be hesitating a bit now and then.
Doesnt feel to me like a misfire. Could it be the fuel?, as it has been in there a long time(3 weeks). And on the way home today I filled the car up with some more optimax and octane booster and first impressions seem much better.
Anyone got any ideas?.
Would resetting the ecu help?.

Just for reference its a 93 wrx.

Dave
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hades

Scooby Newbie
Joined: 25 Aug 2003
Total posts: 104
Location: the edge of the cotswolds . . .
Age: 30
Gender: Male Posted: Fri 05 Dec 2003, 20:20 Post subject:

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Optimax does supposedly degrade over time - maybe lost 1 or 2 ron over 3 weeks. Occassional hesitation can happen because of low octane, so if the problem doesn't come back, I'd put it down to that.

I don't know how quick the 93 ECUs re-learn the advance etc, so don't trust me too much on this, but: I'd suggest if it is getting better, leave it alone. If it's still messing about, worth trying a reset.

Not a lot of help, I know, but at least I answered!
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roboscooby

Scooby Geek



Joined: 28 Nov 2003
Total posts: 1629
Location: On Here
Gender: Unknown Posted: Fri 05 Dec 2003, 20:20 Post subject:

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That is a hypothetical question.

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Big Bear

Scooby Nutter



Joined: 06 Nov 2002
Total posts: 875
Location: The garage putting another engine in the car or is it a gearbox
Gender: Male Posted: Fri 05 Dec 2003, 22:21 Post subject:

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Might be worth removing the two original coils and looking to cracks in the plastic , when I had to change mine all 4 were shagged

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Dave11980

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Joined: 19 Jan 2003
Total posts: 683
Location: Bristol
Age: 23
Gender: Male Posted: Sat 06 Dec 2003, 18:49 Post subject:

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i had all 4 changed when it went it, they did say it may be a faulty coil so i will keep my fingers crossed for that.
will let you know what happens.
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darkerhorse

Scooby Newbie
Joined: 14 Mar 2004
Total posts: 1
Location: cornwall
Age: 37
Gender: Unknown Posted: Sun 14 Mar 2004, 21:35 Post subject:

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Hello

First post in the zone but I do feel your pain. After replacing 4 coil packs (three were cracked) the problem was still there. I discovered to my horror that the importer had taken the CEL bulb out of the dash. Replaced bulb and the knock sensor was faulty. My garage said they never had to change one before £98 on a MY95 WRX. The car was transformed fantastic pick up no lag and no stuttering. A total of £670 to fix problem. The knock sensor is about the size of a matchbox. However car now sold replaced with a very nice 2ltr sport. Hope you sort the problem.

Darker

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Dave11980

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Joined: 19 Jan 2003
Total posts: 683
Location: Bristol
Age: 23
Gender: Male Posted: Mon 15 Mar 2004, 19:12 Post subject:

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welcome to the group. yeah problem solved, it was a camshaft sensor not working at the engine end. information sent to the laptop was fine it was what was being sent to the engine. Still after lots of time spent on it all is well.
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Jolly Green Monster

iTrader: (4)

Crank sensor is most definitly effected by heat as the common sign is that the car will not warm start.. a clean usually holds it off for a while.

As the cam and crank sensors are very similar (identical?) I would expect the cam sensor to be effected by heat too.

I have a spare but not sure if it is cam or crank but can check..
I'll bring it on Sunday if or use to you?

Tried cleaning the sensor?

Simon

Pavlo

I have a pair with me and we (Rob and I) are going to swap.

It's one of the things what I carried over from old engine setup, and that had starting problems too. It's also one of the things that could be damaged when disturbed, cables being potted into body of sensor and all. However my concern was that the engine wouldn't run at all if they were the slightest bit fault, this would appear not to be the case though and I have my fingers crossed.

Paul

Jolly Green Monster

iTrader: (4)

Well here's hoping that is all it is and that would be a nice fix to the problem!

I know they are magnetic and with the crank as they get old they get less magnetic and so the build up of the crap on them stops them working so well, especially when hot.. hence the hot start problems.. presume the cam would fail in the same way and miss the odd rotation of the cam etc..

Simon