Help with trouble codes please???

[SilverLS]

Check Engine light has been on for a while so I got the Launch Creader (thanks to suggestions on this forum) and checked the code(s).

Code 0440 Evaporative Emission Control System Malfunction

History - Had this checked at dealer twice. The replaced the EGR valve (I had cleaned it several times in the past so I went along with replacing it). After they replaced, CE light came on next day. Went back following week and they said the gas cap code came up. They erased the code and did nothing. Next day light back on. It's been on ever since (about 3-4 weeks).

Code 1870 Transmission Module Unstable

History - Check Trans light came on about 3 weeks ago. Stayed on for three days then went off. Hasn't come on since. Transmission feels normal. I've never had any maintenance done to the transmission. The fluid level has never been checked, filled, or flushed.

I could really use some opinions on what to do. I don't want to just drop the car off and be at their mercy. Thanks for the help!
1999 Isuzu Rodeo LS V6 2WD.

Thanks!

[amigo-2k]

Originally Posted by SilverLS

The fluid level has never been checked, filled, or flushed.

That could be the problem with your tranny.

Also, I would clean up the ground point on the alt (big wire that goes to the alt grounding bracket).

Isuzu do funky things with weak alts, battery's and dirty groung connections.

[rodeo02]

The EVAP system code has absolutely nothing to do with the EGR system. If the dealer charged you for EGR system work for an EVAP system code, they ripped you off . Things to check for EVAP system codes: 1) Make sure your gas cap seals & you dont smell gasoline vapors anywhere around the truck. You need positive pressure in the tank (zero leaks) for the system to work. 2) EVAP purge soleniod is inop. 3) You have a tubing leak on EVAP system. The system schematic is shown on a label on the underside of the hood. Most of it is located under the rear of the truck above where the under-mounted spare tire is.
Never having done any maintenance on your 4L30E trans could be a problem that cannot be reversed at this point. These transmissions need ATF changes *about* every 3yr/36Kmi. It's possible the problem is just a dirty range switch (external part), you never know!
G/luck
Joel

[SilverLS]

"1) Make sure your gas cap seals & you dont smell gasoline vapors anywhere around the truck. You need positive pressure in the tank (zero leaks) for the system to work. 2) EVAP purge soleniod is inop. 3) You have a tubing leak on EVAP system."

Would any of these situations pose a problem? I mean, I don't care if the little yellow light is on for a leaky hose or something. I just don't want to leave it if it's going to cause a bigger problem down the road.

As far as the EGR valve goes, I've had it cleaned out twice. Once it was to the point that the car would barely run. Mechanic said it was in bad shape and was "at 40%" whatever the hell that means. I figured it needed to be replaced anyway, so what the hell.

[rodeo02]

The EVAP system (evaporative emissions system) basically just prevents fuel vapors from going directly to the atmosphere. Running your truck with an EVAP system code shouldnt lead to any other issues. Obviously if you smelled fuel vapors, for your own (and others) safety, you'd want to get that fixed. Your truck also may not pass state inspections if the light is on. Are you showing EGR codes with your code scanner? It sounds like you've got the EGR system cleaned out. Post the codes you have. We'll get to the bottom of it yet !
G/luck
Joel

[SilverLS]

Part of the reason I bought the code reader is so that I can reset the "check engine" light just before I pull up to the emissions testing station.

CE light came back on yesterday. Same code (440) as before. The Transmission code (1870) did not come back however - but I will definitely get the fluid flush/filled.

I think the alternator could have something to do with the evap code. I'll clean up the ground point this weekend as Amigo-2K suggested. Maybe I'll ge lucky and that'll take care of it.

I've learned so much about auto repairs since I bought an Isuzu. For some reason I didn't get nearly as much experience when I owned my Honda & Nissan (sarcasm)

[rodeo02]

I doubt your P0440 code (EVAP system malfunction) is caused by an engine compartment grounding or a low voltage issue. I've never seen a P0440 caused by that. I'd crawl under and inspect the electrical connections on the system. It's all easily accessable. Do an ATF exchange on your trans ASAP. I would also do a pan drop & filter change after the exchange.
G/luck
Joel

[2eyefishclaw]

P1870 = transmission component slipping
fludshing the tranny and clearing the DTC usually takes care of this concern if not the torque convertor may be falling apart

P0440 usually a loose fuel cap but I have replaced a few purge valves for this concern