If you had a couple mechanics tell you the engine mounts are toast, well then you already have your answer. Motor mounts are generally not expensive so get them done first. Also 60psi is sky high for a 90 Corolla, the factory recommend pressures on the door jamb are in the neighborhood of 30psi.
diesel engine knock on cold start goes away after like 3 minutes
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here is the video of the corolla knocking upon cold start:
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If i turn the air conditioning while its knocking the knock goes away
Crack each injector to see which one is making more noise. It could be a sticky injector.
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I put in new inyector nozzles and calibrated inyectors less than 10000 kms ago.
Well crack them and check anyway.
Sounds somewhat decent to me, but the last diesel I had was a 1998 Fiat TD, so maybe I'm not up to real standards.
Also sounds like the idle is really low, which could explain why the knocking disappears when AC is turned on. How is the timing handled in this engine, is it a mechanical system, electronic?
Are all the glow plugs in good shape?
Otherwise I'd check the injectors too...and yeah engine mounts but that was already discussed.
Appears to be not firing on all cylinders. Without the glow plugs energized it's purely compression ignition, and compression is lowest in a cold engine at idle. Turning on the A/C increases the idle speed which helps. That could also be achieved by pressing the fuel pedal or turning up the idle screw. Whatever you do don't let it sit there and shake for 5 minutes. Start it up and drive.
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It seems that the cold idle is too low upon start and thats why if i turn on the ac the knock goes away. funny thing the hot idle is too high, i have the hot idle a bit high because the alternator doesnt charge well so the idle got turned up to charge better.The timing is done on a denso rotary injection pump fully mechanical. How can I adjust the fast idle, which is the cold idle? How can I check the glow plugs? Could it be a fuel pump issue? I am going to send this video to a mechanic and see what he says.
The fast idle is the idle when the vehicle is cold. If I am not mistaken the fast idle is set at a higher rpm than the regular idle?
The fast idle is the idle when the vehicle is cold. If I am not mistaken the fast idle is set at a higher rpm than the regular idle?
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JHZR2
Staff member
Start with the basics:
- All glow plugs good and around the same resistance?relay actually work, etc?
- when were the injectors popped and balanced last?
- injection pump timed correctly?
- overflow valve and feed pressure correct?
- no air getting in the system?
- All glow plugs good and around the same resistance?relay actually work, etc?
- when were the injectors popped and balanced last?
- injection pump timed correctly?
- overflow valve and feed pressure correct?
- no air getting in the system?
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I have also noticed that since changing the right headlamp the glowplug relay starts clicking repeatedly with key in
Ignition not just one click of glow plug relay like before.
Ignition not just one click of glow plug relay like before.
Just pull the glowplugs out and test them across a battery, they are very easy to get to. It may have a cold start device - are there any small coolant hoses going to the injector pump ? These will advance the timing and increase the idle speed, and come back to normal when it heats up. You must hold this back with a 10mm Allen key between the arm when checking or setting the timing, as it will advance the timing about 10 degrees.
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I saw these instructions from the 1c engine factory manual
I adjusted the fast idle idle screw as per manual instructions but then after adjusting the rpms went too high and i had to adjust again.
I adjusted the fast idle idle screw as per manual instructions but then after adjusting the rpms went too high and i had to adjust again.
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i will check today with cold start
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I set the fast idle screw as per instuctions with 0 mm clearance as temperature is 90 degrees fahrenheit and knock went away with cold idle though when I turn on air conditikning the engine revs started climbing like to 4000 rpm 5000 rpm way too high. What is going on? Am I doing something wrong?
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Which of these two screws on the pump is the fast idle screw?
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So it appears that the injection pump, which is a denso ve4 rotary type, doesnt have a automatic cold start device, acsd, which is a thermowax element that advances timing and raises idle when cold. I see there is a blanking plate where the acsd would go.
I wonder if the fast idle screw would still have an effect on the engine without the ascd installed.
I wonder if the fast idle screw would still have an effect on the engine without the ascd installed.
Maybe they considered Nicaragua warm enough?
I'm not familiar with that kind of pump, sorry.
I'm not familiar with that kind of pump, sorry.
Something about the automatic change from fast to slow idle is not working if it can't be adjusted.
I see there is a vacuum diaphragm actuating the fast idle screw (which is 1 in your picture). These elaborate vacuum control systems found on cars of that late 80s era often fail, are difficult to troubleshoot, and parts are unobtainable.
You're really expecting a lot from this 1990 Corrolla. Most people would simply goose the fuel pedal to keep it going.
I see there is a vacuum diaphragm actuating the fast idle screw (which is 1 in your picture). These elaborate vacuum control systems found on cars of that late 80s era often fail, are difficult to troubleshoot, and parts are unobtainable.
You're really expecting a lot from this 1990 Corrolla. Most people would simply goose the fuel pedal to keep it going.
