Weird firing problem

**LeeRoy** · 18-05-2006, 01:38 AM

It could be something that's playing up that affects all sparks. Like the CAS or whatever. Is the engine hot?

- LeeRoy

**whatthe?** · 18-05-2006, 01:40 AM

Originally Posted by oldcorollas

tried putting a timing light on it? are the timing marks on the crank pulley? can the CAS slip out of adjustment?

could try unclipping injectors one at a time and see if they all make a difference to rpm?

Timing marks on crank pulley line up perfectly with timing cover and cams at TDC. The CAS was a consideration but would it cause irregular cranking? Unfortunately due to stupidity (leaving breaker on crank and then turning key) my starter is fubared and whilst I have another here I just cant be bothered changing it at 1.40am in the morning. Thanks for all the help guys.
What I really want to know is what are the possible causes (aside from engine timing) of laboured cranking?

**whatthe?** · 18-05-2006, 01:41 AM

Originally Posted by LeeRoy

It could be something that's playing up that affects all sparks. Like the CAS or whatever. Is the engine hot?

- LeeRoy

Nope, drove the 15 odd km back from WSID with no problems, albeit with a lack of power

**Vios-GT_07** · 18-05-2006, 01:47 AM

erm.. are u sure it's firing correctly? each coil is giving off spark at the right time so to speak? aside from the timing check and all that...

i remember a stuffed up dry cell battery caused something like that on me old AE92... it wouldn't start properly and once started just whined and wouldn't rev.. it was as if something was loading the flywheel something heavy

**whatthe?** · 18-05-2006, 01:52 AM

Well, I'm going to try a new coil pack and igniter that I have sitting around once I change the starter so I guess we'll see. It's an odd one...

**LeeRoy** · 18-05-2006, 01:57 AM

Ok well bed time for me. Let us know how you go and what it turns out being

All the best - LeeRoy

**Hydra** · 18-05-2006, 11:24 AM

Actually, one thing that nobody has mentioned... diagnostic codes! They may reveal something

**kingmick** · 18-05-2006, 11:33 AM

Originally Posted by whatthe?

Went off to the drags tonight, finished a run and noticed that my car sounded like it was running on 5 cylinders. Took it home and unplugged each lead from the coil pack, every one made a difference to the idle. Checked the plugs, all fine. The car also has developed a starter motor rythym similar to a car with really bad timing, sort of turns over slowly once then 3 quick turns than another slow one etc.
By these symptoms is it likely Ive slipped a tooth on the timing belt? cant think of anyhting else......

yes can be if you had plenty of grip of the line. we had to chase this problem for half a year on a turbo V6 with a long belt! added 4 tensioners but still jumped of the start line as we use 12inch slicks. in the end i came up with offset cam pulley and ran two seprate belts!
you can hear it straight away when it jumps a few teeth. very flat sound.
you must be getting good grip and or the tensioner was a bit loose.

**whatthe?** · 18-05-2006, 05:05 PM

Nope, fraid not, compression tested it after replacing starter this morning, not one iota of pressure in cyl 4, wouldnt even move the needle on the tester. I guess I'm probably looking at a holed piston

Lucky I have a set sitting in the garage but it's a pain in the ass of a job. Ah well, thats what weekends are for isnt it?

**30psi 4agte** · 18-05-2006, 06:32 PM

spewin!!!!!!!!!!!!!!!!!

**LeeRoy** · 18-05-2006, 06:36 PM

Well that's definately no good

.So whens this nice new motor getting dropped in?

- LeeRoy

**Hydra** · 18-05-2006, 06:46 PM

Damn!! That sucks mate

Good luck - I hope things work out best!

**whatthe?** · 19-05-2006, 12:47 AM

I have another set of standard GTE pistons in the garage so provided the bore is ok it should be up and going again by next week. The new engine should be in within 3 or 4 months, but thats a big job as the car will be re-sprayed at that time, have an autronic fitted, completely new IC and 3" IC piping, custom exhaust and intake manifolds, battery relocation to boot, GT35R, R154, twin plate clutch etc etc etc. So it's unfortunately not as easy as just slipping the new motor in to replace this one.