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2001 gmc safari p300 code repaced plugs rotor cap intake gaskets still runs poorly maf was changed also

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  • peter kurzawski Dec 07, 2012

    battery good fuel pump presser good pcv was repaced



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SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

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Posted on Jan 02, 2017

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SOURCE: Running rich and lean

the codes ur getting will be thrown by a vacume leak make sure u dont have a vacume line leaking or split also check ur pcv valve for clogging

Posted on Jun 18, 2008

  • 68 Answers

SOURCE: 1991 gmc sierra wont start

There are so many things that could have caused this problem to occur. Here are some of my suggestions:

1. Blockage in the air supply to mix with the fuel. Throttle body might need cleaning

2. Compression in the cylinders might be low, probably due to large ring gaps. If you can get your hands on a compression tester to check the compression values of each cylinder, so as to ensure they are in operable range. By the way, was the vehicle smoking heavily when in operation?

3. Is your battery giving a good turn over of the engine? A weak battery can cause an engine not to start. The engine would turn over but just won't start. (Is the engine turning over when you try starting, or does the engine not responding when turning the key?)

4. Igniter in the distributor might need electrical checks to ensure proper electrical circuitry. Liaise with an auto-electrican about this.

Posted on Dec 29, 2008

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SOURCE: 1989 GMC 2500 5.7L - engine surges and stalls at idle. Loses power at cruising speed.

Wow you have replaced a lot of stuff. Lets go back to the Fuel pump. When you replaced it did you replace the hose between the pump and the sending unit. These are common for splitting. Have you hooked up a fuel pressure gauge to check what pressure you have? It should be real close to 13 psi and should raise to at least 18 or 19 when you pinch off the return line.

Posted on Jun 02, 2009

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SOURCE: 2001 GMC Safari. Changed spark plugs, rotor cap

Try changing the fuel filter and checking the fuel pressure at the shredder valve. The readings should be 60 to 65psi with the fuel line pressurized with the engine not running, once the engine is running. It should drop by 5psi. Start with the simple things first. Keep me posted, be glad to help.

Posted on Jun 28, 2009

  • 6 Answers

SOURCE: stalling

I am dealing with the same issue. I have had the computer checks and there is nothing to indicate an issue.There were no computer error codes yet I stall at red lights.

The O2 sensor, the speed sensor or the MAP sensor may be one of the problems. The MAP sensor measure the air pressure in the manifold. It is commonly mounted on the fender and is low in cost and easy to replace. To test it if your if your car won't start, unplug the electrical connection from the MAP sensor. If it starts, then you know to replace the MAP sensor. The Hall Effect sensor can fail and not set an error code. This is an inespensive part that sits underneath the rotor in the distributor cap on cars without distributorless ignition. This only applies to cars made after 1996. Also check the fuel injectors and fuel filter.

If you have a burglar alarm, make sure that it is not causing the problem. It often times can cause the stalling issue.

Posted on Jul 18, 2009

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1 Answer

How do I tune it up?

Oil Change & Filter
Transmission Fluid Change & Filter
Fuel filter
Air Filter
Plugs, wires/boots, cap & rotor if applicable
Clean the MAF sensor with MAF spray.
Clean any debris out of the air intake box.
Run some seafoam in the fuel to clean injectors.
Check tires & pressures.

Sep 28, 2015 | GMC Canyon Cars & Trucks

1 Answer

Why does my 2.5 GMC sonoma truck skips or misses?

Worn timing belt or bad map sensor, weak ignition coil, worn distributor gear (usually starts hard with that) Leaking manifold gaskets all possible causes. Start with a new coil, spray starting fluid around manifold gasket while running, if it revs up in any certain spots, manifold leaking (intake only test), check vacuum lines for cracks and leaks,(MAP) replace sensor. Over 75,000 miles probably timing belt, recommended change interval is 60,000 miles.

Jul 20, 2014 | 1990 GMC C1500

1 Answer

Diagnostic code p300

means random misfire. (really means weak combustion x4)
ever change that slipped cam timing belt?
if the belt slips, compression likes to drop from 180psi to 80psi
as the retards to H3LL.
missfire can be caused by 50 things. but is just 4 in physices
1: bad 12vdc power to the EFI system (and spark)
2: low engine compression, Tbelt is top fail. on all 4 too.
3: bad spark (150k on spark plugs? and friends) tuneup time?
4: bad fueling (to much or too little fuel mix)
there are tests to do. ask'

a dirty maf can cause lean fuel ratios and 300s. easy
clean it from 12" far, or you will damage it. the part is $1000 as suz.
and rising./. or $300 for rebuilt so treat it like plastic gold.

more common causes, not guesses, based on 5years data.
a: low fuel pressure, 15 not 34 PSI. Gauge test is easy, ask.
b: all spark plugs end of life and the wire sets, or rotor/cap bad.
c: MAF is weak, reads too low air flow for reality, (dirty hot wire)
d: EGR stuck wide open, seems they all do at 50,000 miles.
e: leaking injectors ore clogged. but the misfire would show which cylinder. and 300s. (eg; 300s and say 302)
f: Main air intake leaks, even cracks in that huge tube. (old car)
lots of others, ill skip them.

the nifty fifty. (and counting)

Jan 21, 2014 | 1996 Geo Tracker 2 Door

1 Answer

My 2001 GMC Safari has been running rough for a couple weeks now.. I've replaced spark plugs, spark plugs wires, coil, radiator, cap and rotor and checked the egr valve, check the maf sensor. Nothing...

Look and make sure your computer is good! PCM could be failing you! Injectors don't really go bad! Also look at you fuel pressure make sure it's strong!

Sep 05, 2011 | GMC Safari Cars & Trucks

1 Answer

2000 GMC Safari van v6 180,000 miles. 2 years running po420 code comes up and reset with a code reader. Works good for that. Slight miss at 60mph plus loaded and pulling, so I drive at 58mph. Then the...

P0101 is the MAF sensor and if it has even a tiny amountof crud on it, it can keep the dar from running. clean with ELECTRONICS cleaner not carb/brake spray.

P0300 is multiple misfire detected. Sound like it might need tune-up parts

P0420 is the catalyst system bank 1 low efficiency.

I would start with changing the plugs, wires, cap and rotor. And clean the MAF sensor with the proper cleaner. Then see if the car starts and idles. If it does then clear the codes. If it doesn't run right then I would suspect the MAF sensor is kaput. The P0420 code can be caused by a poorly running engine.

Dec 31, 2010 | GMC Safari Cars & Trucks

1 Answer

1999 safari van 4.3 6 cyl. has a service code PO

P0301 is a DTC code that indicates a misfire to cylinder one. It could be a bad spark plug, spark plug wire, rotor and cap, a dirty fuel injector, or the worst a bad head gasket. Cylinder 1 is the first cylinder on the drivers side, towards the front. Start with the simple and check the spark plug wire and add fuel injector cleaner to the gas tank. Good luck and hope this helps you get you van running 100% soon. If that did not help, then your going to have to do a tune up by replacing the spark plugs, wires and rotor and cap. You can get all the parts you need at Auto Zone and they can give you the step by step to get the job done with common tools in under 2 hours of your time. Keep me posted, be glad to know you got your van running 100% again soon.

Oct 27, 2009 | 1999 GMC Safari

1 Answer

2001 GMC Safari. Changed spark plugs, rotor cap and distributor. Started and ran fine. After 6 or 7 restarts the van died down like it was going to cut off and then ran fine. After shutting it off it won't...

Try changing the fuel filter and checking the fuel pressure at the shredder valve. The readings should be 60 to 65psi with the fuel line pressurized with the engine not running, once the engine is running. It should drop by 5psi. Start with the simple things first. Keep me posted, be glad to help.

Jun 28, 2009 | 2001 GMC Safari

1 Answer

96 dodge caravan 3.0 has p300 and p306 codes,

A P0306 code means that the the ECM has detected that one of the engine's cylinders is not firing properly. In this case it's cylinder #6.

A code P0306 may mean that one or more of the following has happened:

Faulty spark plug or wire, Faulty coil (pack), Faulty fuel injector, Burned exhaust Valve, Poor compression, and Defective computer. 

Check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the Caravan, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). The number six cylinder is the one towards the radiator and drivers side. If you are going to change all the plugs and wire keep me posted, be glad to help. Good luck and hope this helps, P0300 just means multi miss fire. 

Jun 22, 2009 | 1997 GMC Jimmy

1 Answer

Running rich and lean

the codes ur getting will be thrown by a vacume leak make sure u dont have a vacume line leaking or split also check ur pcv valve for clogging

Jun 18, 2008 | 1995 GMC Safari

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