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Engine light comes on when engine is hot. Power is the greatly reduced. When engine is cold it drives perfectly. Toyota 7afe 1.8 litre fuel injection, modded aspirated. I've rebuild the motor due to a big end bearing knock which was caused by a faulty/ pirate oil pump. Engine starts, idles, revs up all the way to 7200rpm, doesn't smoke and has no abnormal noises. Its perfect. No loose plugs no leaks. Sufficient oil pressure. But when driven and the engine is hot (driven hard or soft or normal) the engine light then comes on and power is reduced tremendously. This also started occurring a week before I rebuild the engine. I initially thought it was the bearing knocking noise interference with the knock sensor. Under light acceleration its fine, under medium to heavy acceleration the car slightly nose dives. Believe me, mechanical function and timing of the engine is perfect. essembly wise. What is the problem?

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You need to overhaul your fuel injection and if does not work you have loose compression on your piston ring . engine top overhaul can help you

Posted on Mar 28, 2015

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There is a possibility that the old motor was not burning properly and you have carbon build up on the O2 sensers. A poorly functioning O2 senser will not allow the Fuel/Air mixture to work as you give it gas under load. You could have multiple O2 sensers too.

Posted on Dec 08, 2014

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Posted on Jan 02, 2017

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SOURCE: 2004 Nissan Quest - Engine chatter/knocking

Ther e is a chance your injectors are leakin g down and there is excess fuel in the cylinders. Not a good thing. So, you fuel pressure and injectors need chkg. good luck

Posted on Jun 09, 2009

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SOURCE: loud knocking or tapping sound when engine is cold

Take our oil pan off from under your car and there should be 4 to 5 covers over a rod bearing. wiggle each one of them and find out which one is loose. take that cover off of the one that is wiggling and get the rod bearing out. order a new one from auto zone and replace it. The knocking in your motor can end up where you will need a whole new motor. so get it done before its to late.

Posted on Jul 22, 2009

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SOURCE: loud diesel knock nissan terrano II head just replaced.

some black smoke comes out when i put foot down and loses power when goiong uphill i have a nissan mistral/terrano 2.7td

Posted on Aug 20, 2009

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SOURCE: engine or transmission knock / rattle upon

I had the same problem on my 2006 Lucerne and it was the engine mount located on the front of the vehicle behind the radiator.

Posted on Aug 24, 2009

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SOURCE: My Toyota Vitz has a

Knocking can be caused by a bad bearing somewhere in the engine. When the engine is accelerated it might go away due to higher oil pressure.

When did you have the oil changed and how many miles does it have?

Is the knocking rapid (5 or 6 times a second) or periodic (1 or 2 times a second)?

Some knocking is due to low octane gasoline if you experience it at highway speed.

Good luck on solving this knocking problem.

Posted on Oct 07, 2010

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old post
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23865545-flsdwf0rx41rbdaez4cmhnol-2-0.jpg end old post day.

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