ebs

Looks like my '84 shark (Japanese spec car - same as US engine and 4 speed auto) is having trouble starting AGAIN! For a while it has been fine, but the problem seems to have come back in a bad way. When I turn the key, it tries to start, but just won't get there and fire up.

If I am persistent enough the car will start eventually, but it can take like 10 tries. It seems to make no difference if car was recently driven or is completely cold (though it normally seems to fire up best in cooler weather).

In an attempt to solve this over the last year, I have:
1) changed spark plugs (to Bosch Super 4s)
2) had fuel injectors cleaned and removed
3) changed spark and coil leads (to Magnecores)
4) replaced relevant fuses (eg, for fuel pump etc)
5) replaced the fuel pump (with a new Bosch unit)
6) checked the throttle body is properly in place/plugged in
7) cleaned carbon/debris around the cap and rotor

What do I do now? I can only think of:
a) have a mechanic test and play with the fuel pressure regulator
b) have my Autowatch alarm/immobiliser disabled and see if thats the cause
c) could having removed the cat cause this (the O2 sensor sits in the exhaust jet stream now instead of the cat)?

Any other suggestions for a problem that comes and goes?

All help is appreciated.

rjtw

I once had a similar problem due to dirty grounds (mine is a US '83). It is a good idea to do periodic ground maintainance anyway... there's a great how-to list in the archives somewhere.

As far as diagnosis, perhaps you can try to narrow it down a bit. For instance, check for spark when it does not start -- if spark seems OK then it is more likely a fuel issue.

I assume you have L-jet with the barn door AFM.

The problem does not appear to be a cold-start/9th injector or warm up regulator issue, so that helps narrow it down too.

Other random ideas: fuel filter, check for vacuum leaks, replace infamous fuel injection relay. In fact I would replace the relay as a routine matter in diagnosing any non-start issue...

Good luck and let us know how it goes!!
Rick

rjtw

PS once it starts -- whether hot or cold -- how well does it run? If it runs perfectly well, that also helps narrow down the problem areas. I wouldn't go chasing after fuel pressure etc. if it runs well once started.

Re the removed cat, I don't believe that is an issue because to the best of my knowledge the O2 sensor is not involved in the startup loop anyway. Furthermore, the O2 sensor does not know if the cat is there or not -- the critical issue is how far downstream from the exhaust ports the sensor is located. And, finally, the start problem is intermittent, all indicating that location of the sensor is not the issue here. Did your starting issues appear to be somehow related to removing the cat?

I like your idea about disabling the alarm too. I once had that problem as well... the aftermarket system installed by my PO failed and totally disabled ignition. I would leave this one for last unless though it is easy to disable the alarm.

Check out the list for a non-start issue on the early cars. There was a thread just a couple of weeks ago explaining part of the start-up sequence, especially involving the role of the "green wire" and distributor (though I believe problems here lead more to a start-and-stall condition).

One more related check you can do is listen for the fuel pump running after a failed start attempt. Just let the engine crank briefly and release key. The fuel pump should remain running for a few moments and then stop. If the fuel pump does not turn on at all, then that indicates a certain set of problems (I believe a bad lock cylinder in the dash is one of them) -- check the archives!!

Rick

ebs

Thank you, Rick, your posts are greatly appreciated. The car always runs fine once it fires up, but getting to start seems to be the issue. Does this impact anything you have said?

Thanks again
Ebs

jetrainor

Have you done the valley service....rubber hoses, idle stabilizer, fuel regulators, etc, all located under the intake manifold. The rubber was so rotten in mine i could put my fingers through....ran like a new car after....that is until a rod bearing went.

87 euro auto (japanese import)

ebs

I havent jetrainor. What does the service include? Thanks.

jetrainor

Have a look at 928 Specialists on line store....look under kits and you'll see valley service....you can run through what's involved by doing a shopping kart.....it involves things like new intake manifold gasgets, vacume lines, rubber hoses, idle stabilizer valve, etc, and i also did new fuel regulators, fuel injector seals,...basically a box full of parts.....before doing that, my car was hard to start, idled poorly....surging....and ran very rich. After the new stuff, a touch of the key and it fired up and ran flawlessly. Pulled the engine yesterday to begin winter re-build project...plan is to rebuild it stock, run it for a while to breakin, and then SC!.....

87 euro auto