1997 Dodge Caravan backfiring


Engine Performance problem
1997 Dodge Caravan 6 cyl Front Wheel Drive Automatic 213000 miles
3.8 Mitsubisi
I have been experiencing backfiring for a time, I have changed the crank timing sensor, but the problem still remains, I have tried adjusting the sensor many, many times, but no better results, it seems to happen when encountering a slight grade while speeding up or when calling for more speed to pass, it seems to be worse when engine is hot, on hot days and while a/c is on
I recently replaced the fuel pump, and have checked for vacum leaks and replaced bad sections, have changed air filter, pvc etc, also had the tranny shift moduel changed
Any advice will be helpful
Thank you in advance
Alan Hanczyc

Do you
have the same problem?
Friday, July 24th, 2009 AT 10:47 PM

2 Replies


Common Problems and Solutions

Most causes of backfires in the exhaust system can be addressed by troubleshooting the reason for the air to fuel ratio imbalance. The solution usually involves checking for vacuum leaks, changing the airflow sensor, oxygen sensor, or fuel filter to ensure the fuel system is functioning properly.

A common backfire situation occurs when there is a small leak in the air injection system that feeds the exhaust system. This can cause unburned fuel to explode suddenly. One of the most common causes is a stuck or faulty air intake or gulp valve near the exhaust manifold.

Backfiring can also occur with a sudden drop in fuel pressure. This may be due to a faulty fuel pump or a plugged fuel filter. Correcting problems in the fuel system usually resolves these issues.

Incorrect ignition timing to the spark plugs is another cause of backfire. Adjusting the ignition distributor, if the engine is so equipped, may resolve this problem. Adjusting engine timing is not difficult and can be done with a timing light by following the timing adjustment procedure for your car. If you do not know your car's ignition timing procedure please visit our car repair manual page. A vehicle that is not timed properly will not idle, run or operate correctly and will often backfire rapidly. On newer cars you will need to scan the pcm to check for CKS (crankshaft angle sensor) and CMS (camshaft position sensor) related trouble codes.


To prevent backfires there are several things you can do:

Change the fuel filter as needed, the fuel filter is a vital part of your fuel system and can cause a backfire(s) if the filter is clogged and not changed regularly. A bad fuel filter can cause low fuel pressure creating a perfect situation for a backfire to occur. Changing the filter is simple and can save gas with improved performance of your vehicle's engine reducing the occurrence of backfires.

Tune up and service your fuel injection system in accordance with the maintenance schedule for your particular car. This ensures correct fuel consumption with the correct amount of emissions. Fuel that is not burned completely will leave ample opportunity for a backfire to occur. These maintenance requirements are associated with other systems on your vehicle. Avoiding maintenance on your car can increase the risk of backfiring and other system malfunctions.

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Saturday, July 25th, 2009 AT 6:11 AM

Check for codes
fix if any 1st
hook a scanner to it and check data
check if you have SYNC between cam and crank
check timing
no need for any adjustment on crank sensor PCM set timing
3.8 or 3.0 engine
Mitsbisi is( I think its) 3.0 with a timing belt check if belt jumped
check fuel pump and do a fuel pressure test

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Saturday, July 25th, 2009 AT 6:13 AM

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