6G Celicas Forums

a friend of mine is having problems with his '99 corolla.... he says its missing at idle and severely lacks power when dropped into gear; its a 1zz.. if any other info would be helpful just ask and i'll see what i can get from him. Thanks in advance.

This post has been edited by d3ath2009: May 31, 2012 - 2:09 PM

Performed a compression or leak down test yet?

Car throwing any cel's?

Don't have the equipment to do compression test and I can run the code checker on it when I get home this weekend... I'll update when I find anything.

ok, so compression is 100 on 2,3,and 4 and 80 on 1.. he also said that the CEL flashes constantly

You can rent one from autozone for $35-45 and when you're done take it back and get your refund. A leak down test would yield better results as it checks alot more areas, but most don't know how to do one or what it is.
If the compression and cel's comeback ok then i would start with the most common and easy fixes such as timing, vacuum leaks etc.

This post has been edited by Takumi-FujiWaraST: May 31, 2012 - 12:16 PM

was that test done at temp or was it cold? thats pretty low...

Those are terrible numbers and the cylinders have more than a 20% variation which at the most cylinders should on vary 10-15% between each cylinder.

Was the test cold and at WOT?

If not let it cool down then re test it dry. Then re test it wet (pour an oil cap full of oil down in each cylinder if it bumps the numbers up a good bit it's his ring's if not look into valve issues or a blown head gasket) the oil temporarily seals bad rings.

This post has been edited by Takumi-FujiWaraST: May 31, 2012 - 1:07 PM

i need to get this moved.. found out its a '99, hence a 1zz instead of a 7a like i thought

Reguardless you still need to do a cold WOT test then compare those numbers to the WET test, it's lossing compresson somewhere and the variations between the cylinders is a bit much.

Post results when you get those new numbers.

you are supposed to do compression testing with the engine fully warmed up. and yes those numbers are very very bad. doubtful its the head gasket because they dont go bad on the ZZ engines (usually) but it could be a broken VVT gear, bent valves, timing way off. there is just way too many possibilities. I havent heard much on the corolla side but in the celica world with 2000-2003 1ZZ-Fe engines, they drank oil due to having bad piston rings. its possible this is the same situation.

update: new plugs and plug wires.. now it does fine at revs, just not so much at idle, especially when its dropped into gear.. at idle, in gear it shakes horribly... can also hear what sounds like loose timing chain.. ideas?

there are no plug wires on the 1ZZ, its a coil on plug

there are definitely plug wires, how else would the spark plug be getting spark? (maybe slight confusion, by plug wires i mean the ones that go from the coil/distributor/whatever it happens to be to the valve cover and down to the plugs)

There are no spark plug wires on a 1ZZ.


None of these guys.


Spark plugs on the 1ZZ plug into these:


Which plug into the harness.

This post has been edited by 95CelicaST: Jun 7, 2012 - 11:04 AM

Yes there are wires on a 1zz(1998-2000) thats the second gen 1zz(2000+) that has COP (Im surprised smaay didnt now that... Oh wait no I'm not... )
P.s. The plug wires you posted are the exact type that go in the corolla
Plugs


Plugs


Plugs


Plugs


Shall I go on or is that enough???

This post has been edited by hatchy_gt-s: Jun 7, 2012 - 1:20 PM

Honestly if you dont know what you're doing then just take it 2 a shop. It's nearly impossible to diag a car over the internet w/o having all the right info. If you really want help I can give you a list of what info would be needed and MAYBE we can help.

This post has been edited by hatchy_gt-s: Jun 7, 2012 - 1:13 PM

99 corollas came with a (2nd gen) 1ZZ so i wasn't sure. but your compression is still way too low. BTW your 1ZZ did not have VVT. there are just too many variable without seeing the car

rings stuck on cyl 1, wet compression test will show this. number is too high for a burnt valve. time to rebuild.