Injector question
#1
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Injector question
My engine has developed a miss lately. It happens after "spirited" driving, when the engine is good and hot. And only at part throttle, with very light throttle application. Seems to be getting worse by the day. It happened maybe once or twice at idle, again when hot.
When the engine cools down, everything is OK till the above-mentioned conditions occur.
My question is, can an injector go bad in such a way that it only fails when hot, or after seeing higher duty cycles?
I mean, if it is a clog type problem, it would happen all the time, so I don't think cleaners/additives will be of help here.
Have you ever seen such a case when the injector fails under these conditions?
BTW, I have the original red (99-00) injectors, and just about 100k miles on the clock.
When the engine cools down, everything is OK till the above-mentioned conditions occur.
My question is, can an injector go bad in such a way that it only fails when hot, or after seeing higher duty cycles?
I mean, if it is a clog type problem, it would happen all the time, so I don't think cleaners/additives will be of help here.
Have you ever seen such a case when the injector fails under these conditions?
BTW, I have the original red (99-00) injectors, and just about 100k miles on the clock.
#3
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This problem started just as I was planning to switch to COPs.
So the plugs, wires and coils are gone, and replaced with Toyota coils and new plugs.
Also, I see 16:1 afr levels when this happens.
And, there would be a problem with two cylinders if it was an ECU related problem.
This is why I was thinking it must be an injector.
So the plugs, wires and coils are gone, and replaced with Toyota coils and new plugs.
Also, I see 16:1 afr levels when this happens.
And, there would be a problem with two cylinders if it was an ECU related problem.
This is why I was thinking it must be an injector.
#6
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I guess it goes lean when the injector craps out.
I have the PcPro cards. Had no problems for about a year and a half. Started happening recently.
The miss happens off boost, so the cards are not even in the picture.
Sometimes hot restarts are kinda rough, too.
If only I had a scope...
I have the PcPro cards. Had no problems for about a year and a half. Started happening recently.
The miss happens off boost, so the cards are not even in the picture.
Sometimes hot restarts are kinda rough, too.
If only I had a scope...
#8
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Problem solved.
Turns out it was a nozzle rather than an injector.
I have a direct port water injection setup as you may know.
And, of the four nozzles, THREE were clogged.
So, all that flow and pressure was behind one nozzle, which was nowhere near sufficient to discharge the water in time.
The nozzle kept on dribbling long after the engine was under boost, till the line pressure was relieved, hence the miss after a hard run.
I will order four nozzles, rotate them once a month, and have the set I pull off cleaned ultrasonically (which I can get done for free) before I reinstall them.
Car runs great now.
Turns out it was a nozzle rather than an injector.
I have a direct port water injection setup as you may know.
And, of the four nozzles, THREE were clogged.
So, all that flow and pressure was behind one nozzle, which was nowhere near sufficient to discharge the water in time.
The nozzle kept on dribbling long after the engine was under boost, till the line pressure was relieved, hence the miss after a hard run.
I will order four nozzles, rotate them once a month, and have the set I pull off cleaned ultrasonically (which I can get done for free) before I reinstall them.
Car runs great now.
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