P0442 code- purge solenoid need help

[longydongy]

'99 Rodeo 3.2L- alreay eliminated gas cap, cleaned EGR tube, IMG seems fine and the truck still runs good.

I have been trying to figure out how to fix this CEL P0442 problem and need some help PLEASE!! I was wondering if anyone knows exactly how to mechanically test the EVAP purge solenoid? Electrically it seems fine but I was wondering if it may be leaking. From what I understand, it should be open when the PCM sends a ground to it. So if I unplug the connector the valve should be closed correct? I checked it with a mighty vac on both ports (not the exhaust port) and it would not hold a vaccum. Does that mean it is bad? I was thinking since this code means "small leak" that when the PCM does it's check it shuts this valve and watches the pressure, if the valve isn't closing all the way it could cause the P0442 code. Am I correct? If so does anyone know the p/n for this or where I can purchase it? I went to autozone and the one they tried to give me was the vent solenoid valve that is at the canister.

I also noticed that I had a cracked hose at the fuel pressure control valve so I fixed that. Could that have been my problem all along?

This is starting to get maddening as the light will stay off for several days before rearing its ugly head again.....

[okmech1]

I had a very similar problem, I think i had a P0440, and also tried to understand the system before I started troubleshooting. The problem I ran into was I would have had to spend a couple hundred on a diagnostic code reader to really test it out. I opted to bring it to a mechanic that knows isuzus well and found that my seal between the fuel tank and pump was leaking. Sure enough, when I removed the pump to replace the sending unit, I pinched the seal.

Not to say this is your problem, but I found it was cheaper to get a quality professional diagnosis, and pulled out less hair.

Did the hose wind up fixing it though? Are you able to view the code and verify it is only 0442 coming on?

[longydongy]

Sorry for the late reply I had given up on this forum as I wasn't getting any help whatsoever. I still have the problem. I was able to borrow a scanner from a friend and determined it was the P0442 (small leak). At this point I have eliminated both solenoid valves/wires and connections by removing the connectors from the PCM and applying voltage and then measuring it at the connector. I have vacuum tested & replaced if needed all the hoses from the canister forward. The only parts I have left is the fuel pressure sensor (checks out good at atmospheric pressure but have no way to apply a specific pressure and check again as the service manual states). And the vent hoses and seals at the fuel sending unit which was replaced about 3 years ago. So I am still pulling my hair out as you had mentioned!!!! I really can't afford to pay a mechanic at this point to diagnose it for me....

[chaswe75]

'96 3.2L
I would have to agree with OKmech. I had a similar EVAP code that was keeping me from passing emissions. My mechanic friend found a leak and cleared the code. He said the majority of time a leak is the culprit. Get a leak detector and check the system out.