Brookelyn

I'm a chick here...but no slouch, so hopefully ya'll will help me out.

I've researched my tush off trying to figure out what is up with my 2004 RX8 (engine replaced after failed compression test about 10k ago & the cat was replaced about 15k ago), but can't find anything further on my latest issue than what I have already done...

My service engine light came on; I took it to the dealership. They told me that it was throwing a P0076 VDI circuit error and a P0443 purge solenoid error. I like to do the work on my 8 myself (dealers don't treat the car as well as I will) so I told them thanks and brought it home. Let me mention it has been idling rough since the service engine came on.

I researched the DIY and took the UIM off to access the VDI valve. The wires to the connector were broken - yes, maybe I did that when I was removing the UIM, but not certain. I soldered the wires and taped them up. Then I tested it's functionality with the "blow" test and voltage test - all worked well. Plugged the sucker back in and tested the voltage again - good. Put the UIM back together and then did the same test with the Purge Solenoid - again, passed with flying colors. The error code went away for a couple of days and the car ran better.

Three days later, service engine light back on. I plugged in my little $20 MaxiScan code reader and it gives me the P0443 code again (no P0076 this time). I pulled the Purge Solenoid off again and retested it - passed. I even manually grounded the solenoid and could hear it clicking after I re-installed it. Also, tested the voltage again and all is well.

The service engine light went off for a day and came back on - same P0443 code. Any ideas? What other issues can throw a P0443 code. Since I fully tested the purge solenoid, I don't want to replace it. I don't think it will help - it's working fine. I'm at a total loss. Begging for some help!

Thanks in advance!!

Williard

iTrader: (18)

Have you checked the seal on your gascap? Also double check all of your vac lines, make sure you have no leak or anything like that.

Brookelyn

Pretty certain it is not the gas cap as it went off for a few days after I tested all the solenoids and re-installed the UIM. I definitely thought of that as I had to replace the cap once already.

Vacuum lines --- any suggestions on how to text for leaks? Smoke test, I guess? Is there a DIY on here for it?

PS - Thanks for the quick reply. Pretty kick-a of you!

RIWWP

iTrader: (2)

Thumbs up on doing the work yourself.

From the workshop manual:
So yes, it isn't the gas cap. The "PCM malfunction" isn't something to panic over, it's unlikely to be that. That is tacked onto the end of every CEL code that involves a circuit that passes through the PCM.

Are there any of those checks that you missed?

Full DTC diagnostics article attached

Williard

iTrader: (18)

Smoke test will def. work. Their are several threads on the VAC lines. https://www.google.com/url?q=https:/...q1ETm1fz58K8Pw This is one of them. if you search you shall find. Whatever RIWWP tells you is more than likely going to be the answer. He is MUCH more knowledgable than me with the 8

RIWWP

iTrader: (2)

Posts moved, please don't post the same thing in multiple areas of the forum.

Brookelyn

Awesome! Thank you for this. I'll definitely try the wiring first from the PCM; I have a feeling that is the issue. Appreciate your help! I'll try to keep ya posted.

Brookelyn

If all else fails...I'll be onto the smoke test next. Ahhh!! Thank you!

Brookelyn

Yep, understood! My apologies, it was a newbie mistake. I couldn't figure out why I couldn't create a new thread; until I found the thread title in HUGE text that informed new comers what to do...only after I had already replied to the other thread. I usually catch on quick, so thanks for putting up with me!

aRX7-7-8

My 04 RX8, also with a replacement engine 25k ago, just threw the 0443 code. Brookelyn, can you describe what finally fixed your problem?

Thanks!

JAMPK

Anyone have a resolution to the Code 0443 issue? My 2004 RX8 has that code with the Engine Light on. I replaced gas cap. What else can I do to get the Service Engine Light to stay off?

aRX7-7-8

Well, this code has been appearing and disappearing for about a year! It is now mostly on, so it's time to fix it! I want to do this myself, and a P0441 is also appearing about half as often. Does the occurrence of both codes point to a more likely specific cause?

Thanks!