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Discussion Starter · #1 ·
I've been told my head gasket may be on it's way out due to the car only firing on three cylinders in the morning.
I've done a compression test and it shows 205psi on all four cylinders,is there any other method anyone knows to check the head gasket without ripping the engine apart?
 

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Wafoo, I assume you did the compression test with the engine hot. And by "in the morning" you mean with the engine cold.

Have you tried compression-testing the cold engine? If you've still got full compression, it doesn't sound like the head gasket. Mine had only a very slight leak and the compression halved on that cylinder.

That of course leaves fuel or ignition as possibles.

Let us know what you find, anyway
 

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sounds like the di cassete to me

want to buy one ? send me a pm

I have one with 6 miles on it
My car was running on three cylinders
thought it was a di cassette ,bought a new one ..no difference
turned out to be a broken valve
got the di casette here in its box....
 

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Please, anyone, correct me if I'm wrong, but I think you can test the DI cart to see if that is the culprit.

With the engine cold, remove the DI, remove all the plugs and push them up into the DI. Remove the fuse for the fuel pump, hold the cart at each end, horizontal and with the plugs downward, the get someone to turn the starter ie try and start the car. If any plug is not firing, it should be obvious from the difference in sparks.

If one plug isn't firing, switch it with another to eliminate a plug fault. If that doesn't cure it, see Ylee

But be very careful with the DI, the voltages are lethal, even just after you switch the ignition off
 

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Discussion Starter · #6 ·
thanks everyone.I don't think it's the DI cassette as it ain't got one,a 93 2000 CSE should but it hasn't,bit of a worry,I tried both cold and warm eng compression tests fine no difference,but the plugs were a bit sooty,so they've been cleaned and re-gapped
 

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Sorry, just assumed it had a DI.

Sooty plugs eh? Assuming you've got a good healthy spark, that just leaves the injection system. It could be the injector nozzles clogging up, especially if you use cheap petrol.

There is something you can squirt into the inlet side to clear the injectors but I can't remember the name- anyone?

Although having said all that though, being a Saab, I'd check the electrics first
 

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If you have a distributor you could still have electrical problems. If the coil, plugs or plug leads are dying or the distributor cap is tracking there may be sparks that are often visible. I've found the best way to find these is to look under the bonnet when it's dark. I've found quite a lot of obscure electrical problems by waiting till it was night before looking. You may not find a rotor arm problem though.
 

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Discussion Starter · #10 ·
Thanks again everyone,but the DI casette thing has me thinking,if the car is a late 93 2.0 CSE surely it should have a DI casette,does this mean my engine is older than I think!
 

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Originally posted by Wafoo:
[qb]does this mean my engine is older than I think! [/qb][/b]
Well, whaddya know? Looks like the EZK ignition system was used all the way up to '93. I assume it was on 2.0i engines only, as I believe the 2.3i had DI from day one.

You learn something new every day. In that case, I'd first and foremost chase ignition problems, as sgould suggests.

And just an addendum to testing the DI cassette. It is extremely important to EARTH all the plug bodies to give the spark somewhere to go rather than breaking down the coils in the DI.
 

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And just an addendum to testing the DI cassette. It is extremely important to EARTH all the plug bodies to give the spark somewhere to go rather than breaking down the coils in the DI.[/b]
Thanks Bill, that's most useful. My Green Flag man certainly didn't earth anything when he tested it, which could explain a lot

By earthing the plug bodies, do you mean wrapping and interlinking each ceramic insulator on each plug with, say, copper wire?
And does the wire then need earthing?
Thanks in advance
 

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Arranging the cartridge so that the metal threads of the plugs are all resting against some unpainted metalwork should do it I think, although you could do it with wire too and yep, you would have to tie the wire to an earth on the car.
 

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wafoo:
Thanks again everyone,but the DI casette thing has me thinking,if the car is a late 93 2.0 CSE surely it should have a DI casette,does this mean my engine is older than I think!  [/b]
Odd, my mid '93 2.0 LPT CSE definitely has a red DI cassette fitted! Judging by the melted look of the plastic plug surrounds I think it needs replacing too
 
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