Stumbling At Acceleration When Warm, Basically Run

[george.bryant]

Recently my car has started doing some funny stuff. Its running pretty rough on startup, kinda feels like its missing or something. And on acceleration it stumbles kinda and feels like a subaru. I've checked the spark plugs and they were ok except for #6 which had quite a bit of oil build up on it and smelt like unburnt fuel. I cleaned them all to see if that was the problem. Put them back in car and started it and it ran good for about 1 minute then started doing its stumbly thing at idle... I had a play with the ignition timing aswell to try to see if i could set it straight, found a good setting for timing with the 10psi that i run so thats ok. But after driving that car for about 20 minutes it just got even more stumbly, but on boost you dont even notice it.

I put a new distributor cap on yesterday aswell. the car is also drinking water slowly. Using about 400ml a day (i just topped it up with more or shell's coolguard). My lead are about 4 months old, one day i noticed they were leaking spark so i taped them up and i never noticed it again.

Is the problem that i need new leads? Or what. I used to get a vacuum or between 17-18 at idle. Now its at like 14-16. Thats why i set the ignition timing. I dont know what to do. I have a feeling headgasket might be cracked somewhere as my water looked very mildly contaminated but my oil looks fine (its about 3 months old).

Help....

Regards, George.

[QUIKBLADE]

Recently my car has started doing some funny stuff. Its running pretty rough on startup, kinda feels like its missing or something. And on acceleration it stumbles kinda and feels like a subaru. I've checked the spark plugs and they were ok except for #6 which had quite a bit of oil build up on it and smelt like unburnt fuel. I cleaned them all to see if that was the problem. Put them back in car and started it and it ran good for about 1 minute then started doing its stumbly thing at idle... I had a play with the ignition timing aswell to try to see if i could set it straight, found a good setting for timing with the 10psi that i run so thats ok. But after driving that car for about 20 minutes it just got even more stumbly, but on boost you dont even notice it.

I put a new distributor cap on yesterday aswell. the car is also drinking water slowly. Using about 400ml a day (i just topped it up with more or shell's coolguard). My lead are about 4 months old, one day i noticed they were leaking spark so i taped them up and i never noticed it again.

Is the problem that i need new leads? Or what. I used to get a vacuum or between 17-18 at idle. Now its at like 14-16. Thats why i set the ignition timing. I dont know what to do. I have a feeling headgasket might be cracked somewhere as my water looked very mildly contaminated but my oil looks fine (its about 3 months old).

Help....

Regards, George.

<{POST_SNAPBACK}>

If it's loosing vaccum and stuttering, have you checked for boost leaks? eg: intake piping and boost gauge hoses etc... that would cause unmetered air to enter the system and cause more fuel to enter to compensate...

Check AFM firstly, pull it off and spray with carby cleaner to get rid of any grease/oil build up from filter... drive and test.

Hmmm, to confirm/deny head gasket, pop the radiator cap and the fluid should be green and not cloudy or be milky white colour... you could also pressure test the radiator...

Hope at least one helps your situation.

Regards,

Grant

[Nathan_G1]

sounds like uv done most of the necessary checks.......i agree with quikblade, cheque ur afm, but u still could have a problem with ur spark plugs, id look at gapping them better or replacing them. However it shouldnt b drinking that much liquid, u could have head problems if its not leaking.

[Col-GTSX]

Yep replace the spark plugs just to be sure... Would not hurt anyways. Also check all connection in the spark area. I mean check all leads, terminals & connections.

Studdering is missing. Remember 3 things are needed to create ignithtion.

1. Fuel

2. Ignightion

3. Air

In your model car i would point directlly at the spark. So check all aspects out in this area.

[Race__24]

I'd look to the plugs, leads and dizzy cap since there is unburnt fuel/build up on one of the plugs. Replace the plugs regardless, once they are fouled cleaning can only do so much, also a bad plug can exadurate a bad lead.

The first test i would try will identify a miss at idle. All you have to do is to remove the lead from cyl. 1, note the change in engine noise, replace the lead and repeat on the other cyl.s. If you remove a lead and there is no change that is the plug/lead you need to replace.

If you lucky enough for it to miss when you are just revving it, lift the bonnet at night and rev away, look for spark jumping from the leads. In particular the one to the plug with the unburnt fuel/build up on it.

I'd guess the coolant usage, if not from a leak, would probably be from the head/gasket. There can be lots of different leaks on cyl. heads/gaskets.

Oil to the cyl

Water to the cyl.

Water to oil

and in some engines it's even possible to leak from the cyl. to the outside of the engine or under the valley cover on a v8.

Check your oil, is it frothey? Usually the water ends up in the oil, from my experience anyway, not with this particular engine config. If the oil is milky or frothy there is probably water in it. Another thing that can give you a clue is condensation on the filler cap when the engine is warm.

If i was you i'd get the missing problem sorted and then see how the water usage goes. It may even sort itself out once the head temp normalizes with all cyl. fireing

[OVADRV]

dude just replace no.6 plug sounds like u have intermitten open circuit at times.Cars come in all the time at work with same problem,wet plug means no spark under combustion pressure.weak spark

[george.bryant]

Too make matters worst, last night after i got everything back together and went for a drive to test it out, it seemed to be running ok. Driving down the motorway i hit 105 and hear something in the back go clunk (not a big clunk but enough to notice it, and sounded like a tool falling off and hitting the ground [but i wasnt using a tool or doing anything to the diff]). It got pretty bad but only at 1550 rpm to 2150rpm on coasting, it was making this noise like a a broken gear, kinda like a clock ticking but also clunking it was pretty mild. Anyway i needed my vehicle so had to keep driving and couldnt really just stop on the motor way.

I drove 15 km to SuperCheap Auto spares to get a new spark plug and lead for #6. As i was pulling into their carpark it started to misfire and was heating up pretty bad. Looked in the coolant bottle and it was pretty gross looking in there. Was contaminated with oil about 10%.

I went and got the lead and plug, i put the lead on and drove home. It was a horrible drive, i was trying not to hit boost at all but i hit it once and big cloud of white smoke shot out the back. I thought "there goes the head gasket". The rest of the drive for about 13km involved horrible noises coming from the rear end (the ticking clunk noise) and and feeling insane amounts of heat coming throught he firewall and my heater system. I pulled into the garage and gave it a little rev and there i saw the white looking steamy shit again. which i experience at pretty much the same time last year on this same motor.

I've learnt alot since then and reckon i could change the gasket and i probly should as about 4-5months ago i sealed a leak with a chemiweld radiator additive as when my old radiator was in the process of blowing up, it caused a water leake between the head and the block and water was spraying out between the two.

Is it worth changing the gasket? I reckon it is since i cannot afford a new motor at the moment.

I have a spare head but i need to get it crack tested, and ive taken out the cam so i need to know how to put that back in and align everything up. The thing that daunts me with taking the head off my motor is that I do not know how to get the timing chain off correctly, or set its timing again. And im freaked out that I wont be able to get it running or something stupid will happen, or that ill get it all back together and itll overheat and blow a gasket again. I know how much of a bitch it is to get the manifolds off these motors (L20et) but i'm on holidays for 2 weeks and i have another car to use so i was thinking id give it a go.

So i was wondering what you guys think?

And was hoping you'd all be willing to advice me on what i need to do.

Regards, George

[Col-GTSX]

Oil in the water

Blowing crap out the exhaust

Rough idle and drive

Seems to me like a head gasket...

Did you do a compression test?

I think you will find you have blow by in 5 & 6 the piece in-between the 2 cyliners is probablly gone.

Also exposing the oil wells to the water jacket. Hense the oil in your radiator. Also you will be loosing water slowlly with a blown head gasket. Not to mention excessive heat from having oil in the water.

Id do a comp test. Then with this info if 5&6 are low then replace the heat gasket. Worst case is the head is worped but this can be checked once off.

Also check for any leakage around the head where it meets the block. This is a good indicator of warping. But i think its unlikelly.

Keep us posted on what u do.

[george.bryant]

did a comp test yesterady and it came back with 120 on all 6 which was the same as a few months ago.

i'm in the process of getting the head off the change the gasket. can someone tell me how to get the chain off and what i need to stop it from falling down into the front cover and such.

[george.bryant]

oh the water has been leaking for months i just never knew where from. but its #1 cyl between the head and block on the outter side of the water jacket

[Col-GTSX]

So you either have a piece of missing head gasket on number 1...

Or the head is warped... Whcih is bad...

Id take of the bottom cover and remove the timing chain completlly. Its the easiest way. Mark the positions with liquid paper before removing these items. Also check your front oil seal while your harmonic balancer is off. Just for future reasons.

[Col-GTSX]

Sometimes..... You will have to speak to a cylinder head reconditioner on Tuesday...

[george.bryant]

if its warped, can i get it planed or something?

[george.bryant]

ill check it for warpage when i get it out later.

[george.bryant]

i think i have a peice of gasket missing as i blew my old radiator a few months and the car overheated really bad