misfire
 

Gooday all finally getting around to address the disco problem getting misfire 1 and 3 cylanders and a 1300 code has new coils and 8mm wires and plugs pulled the plug getting good spark and it was wet with gas i have new upstream o2 sensors however prior to this happpening i had a rattling cat going to get a compression tester and do a test any use in doing a cooling system pressure check?thanks

oops truck has 156,00 fault free so far

If you have access to them, they are both good test to be done at that milage anyway

Hi everyone well after chasing round all afternoon i was unable to rent or purchase a coolant pressure tester with an adapter that fit i `will do a compression test tomorrow,,,,,just to see where things are,,,,,,thing is with this millage should i maybe just go ahead and tear it down?the truck is off the road and garaged,,,been a good truck this far quick question should i still go ahead and warm it up with the obvious misfiring or do cold thanks:)

hi all got a compression tester is pulling the 30 amp fuse for the fuel pump enough or do i need to locate and pull the relay as well thanks

did the test cold as i had the plugs out for inspection will do again after warm up very consistent just under 150 passenger side bank all the same and 130-135 drivers side

I think I read that the pressure test that advanced uses fit LR, not sure I have one from HF.
but it would be interesting to see what your final numbers, are already you have 10% difference from right to left.

Thank you for your reply i am going to redo the test warm and will post after should i get the necessary fittings to do a coolant system check?want to rule out slipped liner as much as possible before teardown no smoke in exhaust...... or will the condition of the head gasket show a slipped liner?

I would also pressure test the cooling system so you don't have any surprises.


on you compression test if you put a table spoon on oil in the cylinder and the pressure goes up substancally then you most likely need rings

Thank you will proceed with that and let you know have a good day

well iguess thats that did the compression test warm on #1&#7 120 still

good morning just a quick opinion here....is there any benifit to doing the cooling system pressure check at this point i will have to drive a half hour each way for a test kit i have no evidence of anti freeze in the oil and no overheating when running just the low pressure readings in the left bank thanks for any suggestions

Are you still chasing the misfire? Do you feel the misfire, as in the engine running rough? Another member told me about a technique he calls baptizing.

Poor water around all the fuel injectors while the motor is running, if the roughness/misfire goes away you need to replace your injector o rings.

If you have the money, buy a pressure tester on eBay. Around $100.

hi yesthank you for your reply almost dont know it at idle only under load and acceleration no vapor in exhaust and oil clean what i came up with as a guess pulling upper manifold question the bracket thats in front of the secondary air passenger side do i have to remove that metal line from the manifold or can i wiggle out:mad:

Not sure what metal line you are talking about. You should only have to remove the nut/studs from the SAI connections to the manifold.

If you are talking about the throttle cables, yes, unbolt bracket and put to the side.

got it double nutted the stud:)

bit out of practice did a lot of engine work in my 20's and imported them a long while back but its coming back im aaaaaa better than 3 times that now

ok upper manifold is off...........question is do i just do the o ring seals or replace the injectors on those two cylinders whats the experience here?????

gooday i have ordered a leak down tester so hopefully can diagnose things here before going any further........i would think i could bubble check the injector o rings while the the cyl is under pressure ???

You could, in theory. A little unorthodox, but it seems feasible.