Hi, all. Well, my Check Engine light cam on again yesterday. I have had a HUGE history of that thing going on since 1500 miles (bought the car new). It is always the code that indicates a small leak in the fuel vapor recovery system (the code is always 611 and I think once I had a 612). Now, I had a big TALK with the service manager of my dealership last time the thing went on. He (the service manager) was very accomodating. They did the usual first (change parts like charcoal canister, check valve, rollover valve, even the fuel tank) to no avail. They had VCNA rep preside over the repairs and I talked to him (he was the one who suggested the new fuel tank). After about a month in the shop and about 56 hours of labor logged to the warranty claim I got the car and the problem apperently was "fixed" by installing yet another new chacoal canister (the one they put in evidently was defective). I did not believe this for a moment, but the dealership represented by the service manager handled the matter with examplary tact. They offered me an extended VIP warranty plan on them (on Volvo, really) to appease me. I figured it's worth another try (they replaced all abovementioned parts except the fuel tank before and the longest the light stayed off is a few months). Now about a month and a half after the saga the light came back on. I was infuriated, but not surprised. I decided to get one of those generic OBDII scanners and see if I can reset the light by erasing the codes. I figured that this will let me pass inspection without having to go through the ritualistic warranty claim. Here's where it gets interesting. I bought one of those Actron thingies at AutoZone ($150). Plugged it in. It showed no codes. I then followed the procedure for erasing the codes. Presto! The Check Engine light is no longer on. So, I must assume that the code that caused the light to come on was not one of the generic "mandatory" codes. Now my question is does anyone know how the Volvo codes corelate to the OBDII codes? I have the Volvo pocket bible that has all the specs and codes. I also now have all the codes that the scanner supports. I would like to be able to correlate them. I also would like to know if any mechanics encountered such a stubborn problem with the 611 code on a '98 S70. this is really getting annoying. I know the service department is at a loss, Volvo rep is at a loss, I am certainly at a loss. Not sure what to do.

Please help or just comisurate. I love the car in every other respect and don't want to part with it because of such a stupid and minor problem. the only thing is that my state will fail me for inspection if the check engine light is on.

Maybe the tech that first looked at your car did not actaully replace the

charcoal canister, but indicated that he did, Trust me (or ask Gary)

The Evap 611 and 612 codes relating to evap system/tank related pressure/vacuum problems has been a nightmare for Volvo techs and customers since day #1 (when they started doing that), '98s being one of the worst years.

Although I've seen a few problem cars (not easily fixed), someone should be able to properly diagnose and fix your car. Besides the VST, there's a pressure guage setup (Volvo tool) to manually pressure test the evap system to see if it's holding pressure. If VCNA's been involved, they should already have done all that by now as they know all about this stuff.

The Volvo VST (used in '98 cars for diagnosing your cars evap sys) runs the fuel system vacuum tests and to my knowledge no generic tool will be able to do that. A gereric scan tool might be able to receive and clear the code (maybe not qa 611?) but I doubt it'd help you or anyone locate a fault with that system so it might be a waste of money for you.

Hi,

I bought the Actron (www.actron.com) CP 9035 model.

This code scanner reads ALL cars after 1996 as it is federal law requiring all cars manufactured after 1996 to have OBDII system.

It is a good investment, $150.00 at Autozone and you cannot lose with time.

It reads and erases codes.

No need for a PC like other systems (which are BTW more expensive to use).

On the long run, I think the Actron Code scanner CP9035 is a good investement and very simple to use.

cn

1998V70

Hi Vladimir,

Here is a response to my post some months back from Abe Crombie:

The fuel tank test pulls a vacuum on the tank. The 611 code is for a large

leakage. The pressure sensor on tank just measures the pressure and the

control unit monitors the pressure during the vacuum phase. The control unit is programmed to identify large leakage if the pressure sensor doesn't report lowering pressure when the control unit operates the fuel vapor canister purging valve to apply this vacuum to tank, lines, and canister.

This can occur if the purge valve is not opening fully on its repeated

operating cycle during this test, if the canister fresh air vent valve is not closing during this phase, if the gas cap is leaking or is not sealed, if the vapor canister is plugged up, or if there is a leak anywhere on the tank or lines. Your dealer needs to investigate more and quit blaming you if you have certainty that the light has not come on when the fuel cap was loose.

It fixed my problem and I hope it does yours.

Brian M.

Did they ever replace your gas cap? If it has a bad gasket, that would produce the code for a loose gas cap. (Maybe I'm wrong about this, but isn't that the same area that is being checked as the vapor recovery system?)

Best I can do is commiserate. My 97 850 has the check engine light on so I went to Autozone to get "one of those Actron thingies". They offered to hook one up and read/erase codes without having to buy it. That's pretty cool, I was reluctant to buy without knowing if it works on my car, and wondering as well how useful just the generic codes are. Anyway, same thing happened to me, it showed no codes. Only difference is using the erase button didn't turn off the check engine light.

I don't know if the autozone tech didn't know how to erase codes or if that particular device can't deal with some of the Volvo codes. You mention a "procedure" for erasing codes, all he did was push the erase button. I didn't get to look at the manual.

The only Volvo dealer in my area is pretty inconvenient to get to so I'll keep looking for something to read codes. Been looking at PC-based scanner products, they cost closer to $300 and again no idea how well they work with Volvos.

Sure like the diagnostic port/flashing LED on my 95.