GMC Misfire And Cam Sensor Codes

Question:
2001 GMC Safari AWD. SES light Code P0300, or P0301, sometimes a P0341. Repairs for this problem -new engine, crank sensor, cam sensor, distributor(3Xs), spark plugs, wires, coolant sensor, aim sensor, tbs sensor, knock sensor. Cap and rotor. the engine will not stay lit, after it warms up. When cold, it runs fine, but after a couple mins. It will stall at idle. Dealership tech claimed that it was a bad distributor, and that it was out of time. So he opened the hold down and turned the unit. Said it was in time, but it ran a lot worse....missed and bucked all the way home.

So i bought a new distributor, and its back to running good at higher than idle speed, but will stall out as soon as i let go of the gas pedal.( when warmed up) have changed all the sensors, plugs and wires to no avail. The tech claimed that the engine was learning, but it did no good. We checked for vacuum leaks with either, but found none. ( a mechanic helped me with this) any ideas? The codes are 300, 301, only one time did i get a 1345. But i think i pulled something to do that. I changed out the number one wires to see if it made a difference, but it doesn't the spark is fine. Help.


 

Answer:
The P0341 and P1345 mat be because the distributor is not in the exact proper location. P1345 is crank and cam sensor not synchronized. The misfire on cylinder code P0301 should not cause the engine to stall, the timing codes would. Going to need to play with the distributor a little. Replacement may have fixed the original problem, but since the timing is off, it acts the same. Or, the engine timing is off- loose chain, etc- If the engine is used with a lot of miles.

Question:
2007 GMC Sierra 6.6L. Warning lights = check engine light. Repairs for this problem = 5 GM dealers with no solution.Question = im only getting 15 mpg and i want to know why im not getting any better fuel mileage.

Answer:
That's actually pretty good mileage for a big truck like yours. Diesel engines aren't known for getting good mileage, especially just doing around town driving or towing. Some things that can adversely affect fuel mileage would be a clogged or dirty air filter, a clogged fuel filter, bad gas, burning oil, or just a poor running engine. Not knowing how many miles you have on the truck, I can't say what might be going wrong. If you've kept on maintenance, and everything seems to run fine, that's probably the mileage you're going to have to live with.

You do mention the check engine light is on, which could pose a problem depending on what the issue is. A dealership should be able to at least fix that part of the problem, after pulling the code from the computer and diagnosing that problem.

Question:
I have a 1993 GMC Safari The front right brake will not release after the brakes are applied. I can bleed the caliper and it releases. When the brakes are applied again it still will not release. I changed the caliper and the problem continues.

Answer:
The caliper isn't the problem on your vehicle. You have a bad brake hose. The rubber flex hose that goes in between the steel line and the caliper will deteriorate over the years and get soft inside. This will result in the hose actually closing up after the brakes are applied and not letting the brake fluid release from the caliper after the brake pedal is released. I would recommend replacing both front hoses as a pair if you do the job, as you can bet the other side is going to go bad soon as well. Replace the hoses and then bleed the brakes and you will be good to go.


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