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QUESTION:
2003 Duramax superduty silverado code 370 no start. Tests keep showing injector control module bad. Replaced module twice. Starts with new module for a short time then quits and goes back to code 370 again. Already Tried: performed all tests for code 370. tests all pass and tree indicates ficm is bad

ANSWER:
There must be a wiring or connection problem if the FICM is only fixing the issue for a second. Are the FICM’s you have already replaced damaged as a result of this? Is there a chip or performance programming on this truck? If so, remove it or return the setting to stock for testing.

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QUESTION:

1998 f150 xlt larriat 4.9 str 6, overheating problem flushed out system and changed the thermostat, It boils over in the overflow tank — no leaks — flushed out cooling system and changed thermostat and coolant ran cool for about 350 miles and then started to climb —

ANSWER:

Sounds like the radiator fan is not coming on when it should or not at all. The straight 6 engine do not produce as much heat as the V series engine as they have less side wall pressure on the pistons, so less friction = less heat. That being said, it takes longer for a straight engine to overheat.

Check to make sure the fan is coming on, if it is not check the fan itself and work backwards to the relay, switch, etc.

Testing with a multi-meter

QUESTION:

2001 Saturn 3.0 car will not fire only has gas pressure when jumping relay and no power down to crank sensor? jumping fuel relay that gives us fuel pressure. but no communication out of scanner and no power to crank sensor?Car will not start or run. We just put timing belt in car and the timing is right on car.

ANSWER:

Make sure all your fuses are good, and if they are …then “This is an indication of a failed ECM/Computer. The computer will need to be replaced and reprogrammed(flashed) at a dealer.” This is assuming the anti-theft security feature has not been set. If this is the case. Disconnect the battery, put ignition key in and turn it to “ON” (not start) and reconnect the battery, then turn key to start and it should be fine.

QUESTION:

I am restoring a 66 mustang coupe with a 289 engine. The front brake has a spring at the top separating the pads. The rear brake has the standard bar about 1” wide and 6” long with end springs.
On the front brake the Shoe Retract Assist Spring (Fords name in the manual) is broken. It is about 7” long with a straight piece In the middle and a spring with a hook on each end. I talked with a local rebuilder and he said this spring is not necessary, that is why I can not find it. 

ANSWER:

According to Carlson Quality Brake Parts ( the manufacturer of the hardware kits for car brakes ) This spring is not available in there all-in-one kits as it was done away with as part of an update to the front brakes. I assume it was because it kept braking. And the dealer you spoke with is right. It is not needed.

Question:

I have an 05 gmc sierra denali with 75000 miles. My ac will blow cool but not cold. It has enough freon. I”ve been told that there is an actuator behind the dash that tells the ac to blow cool or cold. They said the actuator is out. What do you think?

Answer:

This sounds to be correct, they are talking about your “Blend door actuator” this actuator separates the A/C evaporator coil and the Heater core to adjust the temperature of your vents. If this actuator is stuck between both, then you will have the situation you described.

QUESTION:

have water leaking out of the left front part of the exhaust manifold on my 1992 chevy s-10 pickup truck, V6 2.6 engine. could it be a blown gasket or a cracked head. what the best way to determine this? what would be cheaper, a rebuilt engine or a mechanic to repair it?
 

ANSWER:

The best way to find out for sure where it is leaking would be to remove the exhaust manifold and then do a pressure test of the cooling system. Sometimes you will find the leak is coming from something that was not even close to what it looked like in the beginning. If you can even get underneath the truck and do a pressure test on the cooling system, you may find that it even has a freeze plug in the side of the engine block under the manifold that is leaking. Or you may be able to see it better with a small mirror on a long handle. If not, then I would remove the exhaust manifold to take a better look. If the head is cracked, it could let coolant come out around the threads of the bolts that hold the manifold to the head, as these bolt holes go in right next to the water jackets in the head where the coolant circulates. Same if it had a blown gasket, except the coolant could be coming out of the exhaust port for the manifold. A crack between the valve seats of the head would also cause this kind of a leak. If you do determine that the leak is at the head, you will need to remove the head for inspection to see if it is a gasket or a cracked head. Sometimes a crack will only show up under pressure, in that case a machine shop will need to inspect the head and maybe even magnaflux it to find any leaks. If you end up needing help to remove the head, drop me a note. Unless the motor has real high miles on it or other problems, it will be cheaper to repair than to replace.

Question:

I have a 1997 Dodge neon DOHC.  After driving about 2 miles, when I step on the brakes, my oil pressure light comes on, but if I rev the engine it goes out. The car is a 5 speed manual with 33,000 on it, it also has a oil leak-about a qt. a month, was going on here.

Answer;

The oil pressure sending unit is bad — replace the sending unit and all will be well as far as oil light coming on the oil leak is a whole other issue.