04 Corolla Misfire/timing

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04 Corolla Misfire/timing

Postby lrr81765 » Tue Nov 29, 2011 3:47 pm

04 corolla, 150K, well maintained. Major Preventitive service done 5K previous by me (Timing chain & tensioner, waterpump, new plugs, FI ultrasonically cleaned), car has been running like a top since.

Started hearing noise in engine area (only under load) that sounded like timing chain. Later that day, car starts stumbling bad. Severe loss of power, and this went on for some time before CEL.

Car is better after restart, for a few minutes.

CEL on first instance, P351 & P0340. NO $06 monitors indicating. Cleared codes, ran engine up to 3K, no irregular valve noise or timing noise, or misfire noted. Once car was road tested, within 5 min @ 35mph, faulted and threw P0351,P0352, also heard noise (possible combustion coming through intake?).

    Physically Checked timing, it is dead on
    Pulled plugs - no arc lines on plugs or DIS coils. All plugs visibly good, equal carbon deposits (remember, only 5K miles on them).
    Checked compression - 120-125, which is low according to Alldata (145 min).

Next steps -
I figure this could be an ignition issue, fuel delivery, or possibly a VVT (ranks low).
Logically, I think that with the engine running well without load, the CPS/CKP are likely good, but will check tonight (its been POURING and I am outside, laptop doesn't like that much :) ).
I will have additional probes (Sec Ignition Pickup, low current p/u) today.

Any guidence on which things to start checking first ? I am (I think) fairly compentent, and skilled with the general operation of the scope and knowledge of the different ECM components, but the folks here are much more knowlegeable.

Posts: 1
Joined: Tue Nov 29, 2011 2:30 pm

Re: 04 Corolla Misfire/timing

Postby sobr » Wed Jan 18, 2012 8:34 pm

Hello i hope this may help if the noise sounds like a rattle it may be exessive play in the vvti unit . If u have tried a wet compression test and results stay the same the problem may be with valves not opening enough. Possible cause for both noise and low pressure is possible low oil pressure . If the system has four individual coils with four wires one of the wires is a power the other a ground the other a square wave form the ecu and the fourth a square wave form signal back to ecu to let the computer know it has fired hope this info helps hope you fix it
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Joined: Sun Jan 08, 2012 9:31 pm

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