Need help diagnosing 3.6 VVT FWD Canada value package.

Vehicle went into limp mode and threw code P078A. Solenoid pack was changed by Action Transmission and still does same thing. Something was then jumpered and still does same thing. Rebuilt TIPM then installed and still does same thing. I'm out a small fortune and still does same thing.

Decided to look into myself and notice that temp guage used to run at 1/4-3/8 and now sits at 1/2. I can remove reset code by disconnecting cables and letting sit and then driving again. Goes into limp mode again and again ONLY after about half hour of driving when engine is hot. Open the hood and it feels HOT…too hot



Changed low fan solenoid and fan works. Swapped out high fan(I think) solenoid and fan works. Replaced thermostat/housing/gasket all comes as one. Replaced Coolant, temperature sensor and drained cooling system but NOT block.

Took for test drive and temp still ran at 1/2 and only went into limp mode after I stopped and shifted through gears to park and then back to drive with NO SES light on. Pulled over put in park and shut off engine for 30 seconds, restarted and it drove fine through all shifts. After about 5 minutes it dropped into shift mode on it's own and SES light came on. Got it home turned it off and let it sit for 10 minutes then started it. SES light came on and took it for a short drive AND it shifted through all gears normally.

The original coolant was red so instead, I replaced it with yellow(What do I care, I’m trying to sell the van and just want to get it running well). Oddly, after driving it for 45 minutes at full temperature, the coolant in the top of the rad and reservoir are still bright yellow like none of the old red from the block has mixed into it. Is this possible? Could it be a blockage or the water pump? Is there a way to test to see if the water pump is working?

Any ideas???

 

Made a mistake. The code is P075A

 

the code is for an electrical fault in the circuit that runs from the tipm to the solenoid pack. Hard to say over the internet...maybe a pin fit problem in the connector to the solenoid pack. A dealer has a transmission simulator tool that is required to perform the pinpoint test for this code...maybe give them a shot at it.

if the van uses a non-pressurized coolant reservoir...the coolant will only mix when....the coolant get hot...the excess flows into the reservoir...it stalls there until the vehicle coolant down and vacuum draws it back into the rad. the only coolant that circulates is the coolant in the pressurized part of the system.

 

The connector fault may be why the mom and pop shop jumpered a wire after the "Transmission Specialist" shop changed the solenoid pack. Nonetheless the I'm still having problems. I'll try to get the van to throw a code again and see if it's still P075A or a new one. I think that I can see codes by turning the ignition on and off 3 three times on a Chrysler.

The coolant reservoir IS non-pressurized so what you say makes sense. Once the engine cooled off though, I removed the rad cap and the coolant at the top of the rad seems pristine yellow like I replaced. I would think if there was any mixing of fluid from the block that by this time the fluid would show some sign of mixing with the red that was left in the block that I didn't drain.

I may have to let a dealer take a look at it. I find that dealers are in it for the money and are very good at diagnosing the most expensive scenario first and working backwards to the least expensive

Thanks again