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Sorry to bother you big man, but you were particularly helpful when I had the 5 cylinder issues and you happened to mention something re: valves.

 

Basically, I cleaned the connector on the injector, I didn't remove all the green but I though it would be sufficient to at least get a contact. I checked to hear for the clicking with the screwdriver trick and it was definitely A-OK. But still not firing on number 5.

 

Anyway went up to the factors and purchased some STP injector cleaner, dumped it in the tank with a full tank of Optimax and went for about a 30 mile run - fairly hard.

 

Came home and it was sweet as a nut, I let it idle for a bit and it never missed a beat. Turned her on again later on that day and back to the 5 cylinder problem.

 

Took her out again today, another wee blast, same thing, minty! 1 hour later 5 cylinders!!!

 

You had mentioned something about a faulty valve - is that likely seeing it is fine at top temperature but shitty when colder? Could it just be a blocked injector? Or perhaps I haven't removed enough of the green muck in the connector!?

 

I know this isn't easy to work out when you're about 400 miles away but any guidance you can offer would be most appreciated.

 

Thanks

 

Pete

Featured Replies

Hiya m8 :)

 

First thing is to do a compression test. Unfortunately it does sound to me as though you possibly have a damaged valve/valve seat, but this will only show up on a compression test/cylinder leakage test...

 

Until that, its hard to give any more advice....

 

That help any?

 

CheerZ,

 

Andy

Sounds like the same thing that happened to mine.

It became more and more difficult to start up from cold and was running like pooh, however as soon as it warmed up it was peachy :D.

I had to have all the valves reseated as there was only about 75% compression in each chamber. Anything less than that and you won't really be able to start her up (if all cylinders are the same that is).

Thanks guys, my mate is a bit of a mechanic but he doesn't really want to touch the Zed - he's into Cosworth's and turns his nose up at mine! He is running a 420bhp race tuned beasty mind!!

 

Anyway he has a compression tester and I am going there tonight to give it a bash.

 

Thanks for all your help :bow:

 

I will let you know the outcome for anybody interested.

 

Pete

Few tips to help avoid any problems ;)

 

When doing the test, to ensure even results, remove ALL spark plugs to lessen the load on the starter. Also, get some jump leads and connect to another running car to maintain the battery voltage. If you don't do this and your battery isn't in tip top condition, then you may find the results get worse as you go through each cylinder, due to the revs dropping as the starter struggles to crank the engine...

 

 

Bleurgh LOL

 

CheerZ,

 

Andy

Good call Andy, I will make it so.

 

If it is the valves - is this a big job? I presume it is but what will I be looking at in terms of cost?

Engine out and replace is ~£750. Then you've got a head rebuild (not toooooo bad I suppose) about £250 parts MAX... Plus of course any other bits you want to do at the same time :)

The garage I usually take the car to is going to do a cylinder leakage test as opposed to a straight compression test - apparently this is a far better way of determining the problem.

 

If it's valves, he reckons he can remove engine and rebuild heads for £400 cash. He's actually done a lot of work on Jap cars and pretty well specialises in them. He's a fair distance away - about 200 round trip but I trust him implicitly.

 

That sounds like a good price to me and will go for it if that's the problem. Now, will I do any further damage driving with fecked valves - assuming there lies the problem?

Hi Pete

I'm sure it's already been suggested but just in case it hasn't, have you checked the coil pack. I had a coil pack go and it would work fine when cold but as the engine warmed it failed.

 

Jon

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