Emissions Question

[mangle]

Emissions Question... Help!

I have a 94 RT/10 with 14,2xx miles on it. 1000+ of that have been added in the last six weeks. 600 of it was driving the car from Boston to DC in 6th gear at 1000 to 1250 rpm.

Last Friday, I failed Virginia emissions. Since it's a pre-OBD-II car, the did the pipe sniffer test. I passed all areas except for hydrocarbons. From what I understand, this is just unburned fuel in the exhaust.

I bought a new set of Champion RC12LYC plugs (the stock ones) that I intend to put in tonight. The car currently turns over a few times before firing, so I figured this would be a good place to start. In light of the low mileage history and previous owners who haven't driven the car hard, I wouldn't be surprised to find fouled plugs.

I also drove it pretty hard over the weekend. Hopefully the plug change and opening it up a bit will be enough to pass. Aside from checking filters and such, does anyone have any suggestions?

Thanks!

 

[klamathpro]

The extended turning over before firing during startup is actually cause by the fuel falling back in the tank because of a common faulty check valve in the fuel line.

 

[UK Viper Nigel]

Have the cats been removed without you knowing?

 

[mangle]

Nope, cats are there. I talked to Chuck Tator and he told me a few things that would help. The man knows his Vipers.

I do have one question though... He told me about the throttle body synchronization thing. Apparently there's supposed to be a button you just push on the side of the adjustor. Mine seems to have a bolt and washer there? Am I looking at the right thing? It's on the right side of the plastic piece where the cable exits the sheath and goes to the throttle butterfly axle thing.

*edit*
I figured this one out... The adjuster buttons had been locked out by a screw and washer. I simply removed the screw and the adjustor worked like normal. The throttle bodies are sync'd now and it seems to idle much better. Perhaps a previous owner was afraid that they'd adjust themselves? Plugs will be replaced tomorrow, along with a few other Tator suggestions. Wish me luck!

 

[22YRSOLD]

I have recently failed emmisions in canada.
What i did was tune up the car. plugs wires.
also try combustion chamber cleaner and a couple litres of methyl hydrate. drive it really hard and see the emmisions results. i have seen a huge change.

 

[ruckdr]

mangle,
You said:

I figured this one out... The adjuster buttons had been locked out by a screw and washer

That is interesting, I did not have those locks on my '96 throttle bodies, but a friend bought a '96 last year and it had those locks.
Maybe someone knows if they come on the cars (Gen1, anyway) and people just remove them and leave them off ??

Later,

 

[Tom F&L GoR]

Those "locks" were a TSB fix. Somewhere I still have the dealer bag.

A small amount of the extended cranking is because the 10-cylinder needs to find TDC before firing. With the 6 + 4 cylinder system, it takes one full revolution to do so. If you crank for more than 2 seconds, then you may indeed have the fuel check valve problem.

Using a mister spray bottle, wet the plugs and wires while the engine is running. If you can create a miss or see the spark jump to ground, you have a weak or bad wire that may be causing the HC problem.

 

[Johann]

Using a mister spray bottle,

Chauvinist!!! Why not a missus bottle?

Just kidding, that's a great tip.

 

[RAYSIR]

High Hydrocarbons are from a poor mixture. It means the engine can't burn or fire the mixture and HC goes up as the mixture goes too lean or too rich. Right in the middle is the ideal mixture and the lowest hydrocarbons. You didn't state which it failed or both high and idle RPM. Pulling off 1 plug wire will make it fail IM test but so will a plugged air filter. If you have the test sheet. If CO is high also it fails from rich run, real Low CO is a lean run missfire and the intake gaskets are good for that. PM me if any question. This what I do for a living. Good Luck