I have a 97 ram. 5.9 motor with an upgraded cam I think 216 @ 50. I also have the M1 manifold and upgraded valve springs.

I purchased the truck from a friend who did most of the work. Since the cam swap, the truck throws misfire codes all over the engine at idle. What's odd is that, the truck has nice power and runs very smooth anywhere over idle.

The cam does have a little lope to it.

Any thoughts on remedying this problem?

 

Is the Camshaft Sensor lined up properly in the distributor with #1? There is a notch on the plate and IIRC a #1 stamped on it. If that is not set properly, that could be causing your problem. Mine was 180ยบ out when I had rebuilt my engine. It's a bear to get to with the engine in the truck, and I had to use a mirror to get it lined up.

 

is the cam computer compatible?

 

What codes are you receiving?

Some camshafts cause the MAP sensor to read too low of a manifold air pressure reading and this causes idle problems. Try removing the MAP sensor ( it's on the front of the throttle body), plugging the vacuum feed from the throttle body, and routing a new vacuum feed from as low on the intake manifold as you can find. Then re-mount the MAP sensor. Between the new Cam and M1 manifold this might not help, but it is a very cheap mod that did fix my idle problem.

 

Codes are probablytoo rich and random misfires? The higher you go w/ duration the more misfire codes you will get and the more your pcm wil struggle to get the idlefuel trims right. It is said that turning your fuel sync up to +6 will get rid of alot of misfire codes.If you have never heard of it before, a company called Split Second makes a device that manipulates the map signal. It's called an ARC-1, and will take care of alot of your idle issues. You need a scanner to tune it right, but once you get it dialed in you can pretty much leave it be. Once you get used to it,It does have a gain on it to tweak wot a/f ratio to varying conditions. All in all, it's a pretty cheap (by comparison) unit that's easily mastered after a few weeks with a scanner and a a/f gauge. Ask your buddy what the exact specs are and post back.

 

Thanks guys. I had read about the MAP mod and I will try that first out of utter simplicity. I am going to thrown a vacume gauge on the TB map opening to see what i ampulling. That was my innitial thought. The cam that was installed was "as told to me" the largest the computer could handle. I am going to have the computer flashed by KRC to account for the cam and the M1. My last resort will be the cam sensor check.

I haven't pulled any codes for too rich. Just missfires fyi.

 

Seriously, double check that she's lined up with #1 on the cam sensor. What's the worst it can do?

 

OK OK....only because my sn should be AUDI and a DODGE. I will double check.


Thanks

 

You might want to consider the Mopar Performance Computer. It's designed to handle mods like this and you'll get more out of them. Better IMO than hacking the stock computer to barely tolerate the mods.

 

From my research, again, tell me if I'm wrong.A custom PCM flash is better than the mopar perf, which is built on averages. And considering KRC i think uses the same base as that chrysler place in mi, i can imagine their PCM work is excellent.