Massive flooding, gasoline almost up to the butterflies in the TBI

GOLDBARON357

MEMBER
1994 CHEVROLET S-10
205,000 MILES

Well. The last place I look for problems is the injectors simply because I've never had problems with TBI. And it isn't easy to crank the engine and look at them spray gas at the same time. So. I replaced plug wires, plugs, distributor cap and rotor. I got two minutes of run time before it stalled out and wouldnt run, blue smoke. Obviously flooded. I had opened the throttle and looked down the throat of my TBI, and well, there is standing gasoline in there just about up to the butterflies.

I had someone crank it while I looked at the injectors in operation. Well hell, both injectors are spraying huge amounts of gasoline during cranking. It took about one second for both injectors to spray fuel alternating back and forth one time each, but each time one sprayed, it was easily 4 to 6 fluid ounces of gasoline in what, half a second's time? I didn't even know those injectors were capable of shooting so much fuel!

So it explains why my spark plugs are soaking wet with gasoline when I pull them out. It explains why its flooding and not starting.

First thing I am going to do in the morning is pick up the TBI kit from Napa. But I want to know if I am on the right track.

I figure the problem has to be with the TBI. I've tested every last ground and sensor that I could reach wiring for.

Is there ANYTHING else that could be causing it? Or is it most likely the injectors being messed up like I figure?

And, I dont know if this is related to the problem at all, probably not. But when I try to access the OBD, no codes flash, but there is a clicking coming from apparently inside the TBI assembly somewhere until I unhook the code reader.

I can't afford to replace sensors AND rebuild the TBI right now, but I wanted to get as much of an expert opinion as possible before I attempt to do anything with it. I've been down this road before, replacing parts until it is fixed, and I'd rather get it right the first time now.

Thanks!

5 Replies

RASMATAZ

MECHANIC
75,992 POSTS

Replace the injectors-start here

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Monday, June 4th, 2012 AT 10:05 AM

GOLDBARON357

MEMBER
7 POSTS

Here's what I did. I overhauled the fuel metering/regulator assembly. New diaphragm, gaskets, pulled the injectors, put new filters, o rings and gaskets in for them too. Put everything back together.

With the injectors disconnected, I cranked it over to see if it would burn all the excess gas in the engine. It fired up, ran for about 20 seconds on all the gas that was left in the engine from the flooding. Hooked up the injectors, and it fired up. I drove it around some until there was no more smoke, and it was running perfectly smooth, didn't even try to miss, except when it was first started.

When I shut it down and left it for about 10 or 15 minutes, I came back, had to repeat the process. It was not firing. Pulled the plugs on the injectors, fired it, shut it down, hooked them back up, and it took right off. Drove it around for probably half an hour, made sure it got up to temperature. Did not even attempt to stall out or anything. I observed the fuel injectors were working properly when the engine was running, and during cranking it seems to be putting a little less gas in than it was, but apparently it is still dumping enough in on a semi-cold start to flood it out?

I shut it off, waited a few seconds to half a minute each time, it would fire right back up. Soon as I let it sit for 5 or 10 minutes, no fire again. And the process has to be repeated to get it to run. I would further note that the service engine light has not came on every time I turn the key to the on position. Most of the time it does, some times it does not.

When I first started it up and all, it wanted to hold its idle around 1,000 rpm. After a few minutes it settled down to 800 or so where I like to see it. There isn't a whole lot of dithering on the tach and the throttle is responsive at all amounts of pressure on the pedal. So I don't suspect the TPS is giving any trouble.

The engine light intermittently working worries me a little.

I will probably still go ahead and put new injectors in just for the hell of it, but they seem to be working properly. What other areas can I focus on to maybe resolve this issue?