anyone heard from this guy?

 

Hey Izero, the mechanic said that what you brought up wouldn't cause these issues and said its a waste of time. So did the mechanic in the bay next door.

I beg to differ. Im picking up the truck tonight and taking it somewhere else. Does any one know a good dodge mechanic in the south florida area? preferably in Palm Beach. I would like a mechanic that will run the tests that izero mentioned. I need this truck back asap!

 

Arrigo Dodge Chrysler Jeep Ram 6500 Okeechobee Blvd West Palm Beach, FL 33411 (561) 683-1511



Napleton's North Palm Auto Park
3701 Northlake Blvd Lake Park, FL 33403 (561) 622-0101



Dodge Dealer is your best bet, you might have to pay a diagnostic fee, but if they find the problem it will be well worth it.


They have the right tools to log those parameters, and check the base timing on the truck.


They will also be able to tell if the Truck puts itself into Limp Mode once you get up to 2,500 RPM as well as which sensors are causing the condition.

 

when you say rev limiter, are you saying that it acts like it's dead or dying, and then picks back up? or, are you saying that it holds a steady smooth 2500RPM?

when you rebuilt, what flex plate did you use?

it may not matter about the ckps, it may be what the ckps actually reads... as in, the contacts on the flex plate are fouled, or God help you, demagnetized...


edited to add: if one or more of those pick-ups are corroded or demagnetized, the truck will operate fine up until a point.. that point is the RPM level where mapping the cranks position becomes stupid critical.. if, at a lower RPM the ckps 'misses' a reading, it can still trust it knows the location of the crank, and therefor knows when to fire injectors.. once the RPM's pick up to a certain speed, the engine knows it's turning that speed but can't determine precisely where the crank is at in terms of mapping it.. so.. the PCM says to it "no you don't, you run at a speed we can map"... hence, what feels like a rev limiter, because it basically is..

you need to swap flexplate/flywheel.. a snap on scanner may be able to connect and see precisely what signals the ckps is sending, and I bet a dollar to a donut that it is missing signals because of a bad sector on the plate..

once confirmed:

there is a tiny port where the ckps fits.. you can possibly get a piece of something abrasive that won't fall apart and scrub those contacts.. basically, you'd hold the abrasive whatever still while someone cranks the engine- pull plugs so it doesn't start.. get those points cleaned up and see what happens... the alternative? pull the engine and trans apart and clean it/replace it... I'd replace the damn thing if I had to go that deep... point is, and chances are: an engine that sits around has a good opportunity to corrode on surfaces like that... that is not a good thing, as you're learning..

 

That is also possible, but then he wouldn't idle very nice, b/c the PCM wouldn't know what the base idle timing was and would likely shut the truck off.

The 03 and 04 Flex plates should be identical...

Only way to tell is to get a data log of what happens. and see what the readings are.

 

if there are eight contacts on that plate, and one is bad- the pcm can triangulate the position with relative certainty.. if there are two bad, it gets harder.. three, ect... at some point the PCM isn't going to be certain about the position due to speed of rev.. one bad sector could cause the PCM to toss in the towel trying to triangulate, and limit the rev- and the PCM would also blame the ckps instead of the flexplate..

 

That will be hard for him to diagnose manually... which is why I am saying he will need to use a datalogger to get all those sensor readings and see what is going on.

Plus once he replaces the crank sensor and sees that it is still happening the next step will be to replace the flexplate.

 

oh, I agree... to diagnose such a thing he'll have to have a scan tool that shows raw sensor data and counts..

the reason I went this direction is because that engine was apart- which means the flexplate/flywheel was exposed for however long...

 

Well hopefully he brings it to a dealer that will give it a full road test with a scan tool.

 

yup... the biggest thing I was trying to impart, is that the ckps may come up on the scan as faulty, when it's not the ckps but where the ckps gets its information... which are the points on that flexplate..