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Discussion Starter #1
Once I sort out a problem, another shows up:-(

I was on a long drive yesterday. When starting the engine after a short brake, the engine was difficult to start and the CE lamp lit. I had a paperclip and list of fault codes in my car, so I found out it was 92-cam position sensor incorrrect signal. I happended to find an Opel store across the street, and they quoted 1600NOK (£120) for a new sensor. I said I'll buy it somewhere cheaper and continued on my trip. The car was in limp home mode, so it felt like 40hp. After my next brake, the CE-light went out, and everything was back to normal. After next brake car was difficult to start and lamp came back. I checked all connections, and the light disappeared again. Is this truly a faulty cam sensor, since it's on and off?

While browsing the forum I also found that faulty crank sensor can cause difficulties with starting, without producing an error code. The car has been difficult to start when cold lately, but except yesterday it starts happily when warm. Could my crank sensor be on its way out as well?

So; which sensor(s) to change? Cam, crank or both? If crank; where can I find my engine number? Two different sensors and I think I need the old one (P/N 90458251), but want to be sure when buying from ebay.

Edit: Should add that the crank sensor wireing appears to be in pretty bad shape.

-Magnus-
 

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Discussion Starter #2
I've done some research during the day, and the fault code appears on warm start, and disappears when the engine is cold started. Doesn't make me any wiser, but perhaps it means something to you guys.

-Magnus-
 

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Both sensors (and yours is likely to be the cam sensor) can become heat sensitive with age, just before they fail completely. When the sensor gets hot, it fails.

We test the cam sensor by spraying it with Freezer Spray when it fails hot. It then springs back to life.
 

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Discussion Starter #4
I tested with freezer spray, but by the time I got it, the light was permanently on, so it didn't work.
I just replaced the cam sensor. A bit nerve wrecking for me, as I've never opened the cam cover. Changed the sensor, but the fault remains:( I haven't done 30 clean starts yet, but since the fault was on and off for a while, I reckon that shouldn't be necessary. The EML goes out for a couple of seconds after start, and then light up again.
The sensor I bought (off ebay) was without wireing and connector, so I guess there's a fair chance the wireing is broken. Is there a way to test the wireing and/or sensor with a DMM? I guess that the engine must be running to test it, but I don't want to disconnect the connector unless you guys says it's OK. What kind of signal should the wires have? Ground and +5V to the sensor and a small signal voltage on the return cable?

Any other suggestions as to what may be wrong? The engine needs to be cranked for a while before starting, both when cold and warm.

Edit: Found out that that the sensor works by pertubation of a high frequency AC signal. Would appreciate ways of testing sensor and wireing respectively with a decent DMM (hopefully I don't need an oscilloscope).

-Magnus-
 

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***VxON Photographer of the year 2007***
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this could be the known hot start problem, the fix could be on this site, if not I suggest visiting www.totalcarlton.com

appologies to the webmaster for recomending another site but it should fix his problem

we are not one of those type of clubs that gets all upset when peeps point to another site for help with a problem :Cool2:
 

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Discussion Starter #7
Thanks mate. The starting problems described in the external link appears to be starter motor. I'm pretty sure that's not my problem. Browsing this site suggests CTS and perhaps crank sensor from what I can see. Some of my starting problems can probably be attributed to my car going on ethanol (needs more heat to evaporate). Well known problem from cold (solved by heavy fuel enrichment), but shouldn't be a problem when warm. Then again, the starting problems aren't huge. AFAIK cam sensor fault disables sequential fuel injection and goes into batch injection. My cold start problems has been there for several months prior to cam sensor problems appeared. I was hoping that solving the cam sensor problem would solve cold starting problems as well. Doesn't know if it means anything, but prior to sensor failure, cold starts where easier when keeping the igniton on for 20-30seconds before cranking.
As mentioned in the second post, the sensor problem started as a temperature dependent one. The starting problems and sensor problems may not be related at all.
Anyone know what the 3 pins on the connector should read if in working order?

-Magnus-
 
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