C4 Injector Removal

BTW, 117,000 kms original kilometers (72, 500 miles) and garaged.

Thanx!

I had a very similar problem in my 1985. It turned out to be a carbon build up in the combustion chamber. The carbon absorbed gas. When the car cooled a little after being driven, it would release the gas, and flood the engine. The dealership had to work with Chevy to diagnose it. They used some solvent to clean out the engine, and it ran great after that.

Hope this helps...

Interesting, which make one wonder how many more deposits are left in our engines with today's fuels. My C6 has the sootiest looking exhaust pipes I ever seen; looks like they did when the choke stuck in the older cars but gets twice the MPG.

run some Lucas Upper Cylinder Lubricant and Fuel Injector Cleaner

Hmmm, tend to think you're on to something. I've noticed more combustion roughness when we go through our annual winter-to-summer gasoline changeover -- and it's been worse out West since we had to give up MTBE. Maybe we're getting some Chinese wheat gluten in the gas.

-- PJ

I'm pretty POd about this gluten business. I haven't lost a pet, but it's driving me nuts trying to keep up with the continual expansions of the recalls.

I'm assuming changing brands of gas for a while to change the detergents in it isn't sufficient.. That these deposits are just to tough/extensive?

AJM '93 Ruby coupe, 6 sp (both tops)

Actual we used a product from Ce-Pen-Co that we metered into the carb to burn out the deposits and kill all mosquitoes in a 5 mile radius. There are cleaners in a pressurized cans that screw onto the fitting on the fuel rail to do it now. Of course there is a GM approved version that is 4X the price that they recommend.

Hmmm.. just spoke to GM and they don't have anything that comes in a can via the schrader valve, just stuff to dump in our tank. Someone else suggested that the O2 sensors can go open loop mode and cause rich buring without flaging a code (ODB1). Could the O2 sensors be causing this as well?

have you even tried to run a good injector cleaner through your tank first ? (suggest the gm cleaner or Lucas Injector cleaner) I would at lease try that before you start replacing the O2 sensors.

Try this out for size (scroll down the page to the paragraph on using an R-12 hose -- you're on your own)

Here's a product. 3M UNIVERSAL FUEL INJECTOR CLEANER, 10 OZ. AEROSOL (08956)

Note that the can has 100 psi of pressure.

-- PJ

WOW, that's wedding night pressure; just what MacGyver needed back in the late '80's. GM says to boost the pressure up to 70/ 90 PSI to clean/flush the injection system.

Dad

your sig reminds me of this joke I seen on another group.

g'day

Have you any idea how many men would work on that bridge??????

Dad

My greatest fear is there is no such thing as PMS and it is really her personality!

I had exactly the same problem for years with my 1986 convertible. The problem turned out to be the fuel pump. Apparently there was a small crack or something that caused the problem. Once it was replaced entire issue went away.

On the output of the fuel pump there's what appears to be a snubber -- Chevy calls this a 'pulsator.' Last fuel pump replacement I did, I just replaced the pump and left the old snubber in place. (IIRC the price of a new one seemed high.)

Wonder what the life of a snubber is and what the symptoms are when it quits 'snubbing?'

Wow, remember the days when you could just pour water slowly down the carb and clean all the carbon out?

Too bad you can't do that today.

(lot of stuff snipped)