2001 Dodge Intrepid Almost stalls then Revs? Code P0601

Hello,

Ok, well lets not be to concerned with the PCM right now. Just because the engine overheated doesn't mean the PCM was affected or any Relays.

The most likely and common cause is the IAC (Idle Air Control) Valve or some call it the Idle Speed Control Valve.

The problem may be a buildup of carbon or fuel varnish deposits.

It can be removed and cleaned first before replacing.
The cost of replacement will be between $73 and $130.

To clean just use some Carb Cleaner and spray into the opening, and clean the Plunger on the Valve itself. Let soak for 5 minutes or so then spray it again. Reinstall and start vehicle rev engine to 1500 for about 2 minutes or if there is any white smoke till white smoke clears.

Below is a pic of Valve.

You can try the Sea Foam. Sometimes with the newer vehicles a large vacuum leak will cause stalling. So, I will usually just remove the valve and clean it. It's a little more work but I think it work a little better cause if there are some pretty good sized carbon depisits you can use a small flat screw driver to scrape it off, were as the sea foam may not get it off, at least not with one treatment. Also there are times when depending on were the Valve is located that would be easier the clean it remove the Throttle Body and you would need a new gasket if you do.

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Ok, misunderstanding with the seafoam thing.

The way I do the seafoam is by removing a vacuum line from the intake or the Plenum and replace with one long enough to read from the vacuum nipple to the can of seafoam then start the vehicle and let the vacuum inhale the seafoam to clean intake or plenum along with valves.

Ok, back to the IAC. Did you try pushing the plunger in to make sure it was moving and not froze up?
Here is a simple test.

To check the IAC motor remove the unit. With the wires connected turn the key to the "on" position without starting the engine. The IAC should move in or out. If the IAC motor does nothing it has probably failed. Replace it with a new unit.

Clearing the codes shouldn't make a difference. Usually once the problem is fixed the vehicle will run normally and the code will clear out after either 500 - 1000 miles or 50 - 75 key starts. But I usually suggest having codes cleared at your local parts store once repair is completed.

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Ok, I believe it should have come back out, but not sure.

The other test will tell for sure though.

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Ok, Let me put your mind at ease about the P0601 code.

P0601 OBD-II Trouble Code
Technical DescriptionInternal Control Module Memory Check Sum Error

What does that mean?

Basically that means that there is an interal fault in the Powertrain Control Module (PCM). There have been many reported PCM failures on Chrysler/Dodge products although it is possible for this to happen on any vehicle. In Dodge/Chrysler products, a P0601 trouble code means that a serial communication failed inside the computer at least 6 times.

Symptoms

Likely, no symptoms will be discernible to the driver, other than the illuminated Check Engine Light. Typically the engine runs fine, gauges work, etc.

Causes

A code P0601 in most cases means the PCM has gone bad. This is possibly due to a short-circuit inside the PCM. Or, if you disconnect the wires/connector from the PCM while the battery is still connected, that may also cause this code.

Possible Solutions

With a P0601 OBD-II trouble code, the most common fix is to replace and reprogram the PCM. In a few cases the dealer may be able to reflash the PCM and get it working. But more than likely the PCM will need to be replaced and reprogrammed (we recommend you take it to a dealership for this). The good news is it *may* be covered under your emmissions warranty. So even if you're out of bumper-to-bumper warranty or powertrain warranty, check your warranty guide or dealer to see if this is covered.

Other people have reported that they cleared the code only for it to return again and again. Keep in mind that most shops can replace the PCM but not all can program it.

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Ok, Now let try a few thing....

First - When was last time Fuel Filter was changed. If been a while may be good idea to change it. A partially clogged fuel filter can cause engine surge.

Next - will need to check Fuel Pressure - Check link below for Video on how to test....

https://www.2carpros.com/car_repair_video/test_fuel_injection_pressure.htm

The next possiblity is the Catylitic Converter - To check you can remove the O2 Sensors in the Exhaust Manifolds and run car if Surge is gone then replace Cat.

Also Recheck for Vacuum Leaks

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Ok, so since you say that it happens on first start only, then if you turn it off and restart it the problem is gone?

Ok, now with a partially clogged filter the pressure going through the filter can fluctuate causing engine surge.

Now, a weak fuel pump can do the same thing.

Also I was referring to the Cat being partially clogged and if you remove the 2 O2 sensors in the Exhaust Manifold and start the vehicle if the surge is gone then you have a failing Catylitic Converter and you will need to replace it.

The PCM being bad, I don't believe has anything to do with the engine surge.

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Glad you are all fixed. Just not sure why the PCM would cause the surge. A bad PCM will go into a default mode and there is usually no drivability issues.

Congrats on the fix.

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