Okay, where do I start? The truck in question is a 1994 S10 Blazer, 4.3L W code, auto trans, 4wd.

First off, it usually takes a couple of tries to start the truck, unless its been sitting overnight. During the couple of tries, I have to pump the gas pedal just to get it to start on the third or fourth try.

Secondly, it barely idles. It runs really rough at idle, though it will continue to run at idle, its just lumpy.

Third, I'm getting about 12 miles per gallon.

Fourth, I have absolutely no power. I kid you not, it takes a good 45 seconds to get up to 45 MPH. Once up to speed it seems to hold speed as long as I'm under 60 MPH. It will not go above 60, unless I'm flooring the pedal.

Fifth, the thermostat opens after about 3 blocks, and it is running around 200-210 at that point.

Sixth, it has an extremely strong odor of gasoline. Almost knocks you out, strong.

Seventh, the manifolds were glowing after a trip on the freeway recently. They were red-hot for a moment or two after I jumped out and checked. I also replaced the spark plugs, wires, cap and rotor, and at this time the wires literally caught fire. I bought some higher quality ones and they have not ignited since, but under the hood is still extremely warm. I have not seen the manifolds quick enough since this incident to see if this is a regular occurrence.

Recently, I have changed the plugs, wires, cap, rotor, thermostat, oil and filter, and flushed the radiator. Nothing has helped.

Please tell me there is a solution, I'd like this thing to make it through the winter at least... I'm sorry if this is a re-post, but I couldn't find any topics with the exact same list of issues as mine,

Thanks in advance,
John K

 

A glowing exhaust manifold could be indication of a restriction in the exhaust system or could possibly be from over fueling. Your catalytic converter could be the problem, but you could also have a fuel leak inside the engine. You should run a fuel pressure leak down test to see if it leaks down.

 

It isn't the cat, it was removed by the previous owner (at least I suspect it was, as it wasn't there when I crawled under it the first time.)

Is there a thread that describes the fuel pressure leak down test and what I results I should get?

 

There are many. The fuel pressure test port is at the back of the intake near the brake booster. You will need a fuel pressure gauge to read pressure. Pressure should rise up to 60psi or slightly higher and then only drop a few psi when the pump shuts off. If it drops rapidly to zero, you will need to pop off the upper plenum and have a look for leaks.

 

Excellent, thanks for the help. Is there a certain type of fuel pressure gauge I need to buy? Is it something I can walk into AutoZone and pick up, or do I need to order it online?

 

the other easy thing for you to check, which i think it maybe be, is the fuel pressure regulater inside the pluemun. all you have to do is remove the plastic vortec cover on the top, then un- plug and remove the 2 screws holding down the manifold tuning valve on top of the intake (the round black thing) and look in there with a flash light for puddling at the bottom of the intake. also make sure to see if you smell gasoline in there . if you do notice these problems, there you found your problem and need a fuel pressure regulator and maybe the spider too....

 

Excellent info, guys. Tomorrow morning I'll be checking the fuel pressure. If it is indeed the Fuel Pressure Regulator (which it does sound like after reading up on it), what should I expect from the Fuel Pressure Test? Is it going to read high or low?

 

make sure you take off the manifold tuning valve and visually look inside for a leak...you dont want gas leaking in there because it will dilute your oil and can damage your engine permanantly....

 

owned 2 of these 94's........the cat and muffler prone too plugging! hot exhaust will melt the muffler together.... other than that the cpi unit being the culprit for it all. but usually its the regulator, not offered as a replacement part but how will they make money if you dont buy the whole spider;/ u can get just the regulator i just cant remember the part number...

 

As said, the most likely culprit is the FPR (fuel pressure regulator), but unlike what is stated above, it is most definitely available separate from the whole CPI unit. You can even get a kit that will use the FPR from the newer SCFI engines which is less prone to failure. The kit is available from lindertech.com. You can check out the instructions on how to adapt your CPI spider to the newer SCFI FPR to see if you have everything necessary to do the replacement. If not, a factory style CPI FPR is available from pretty much any autoparts store.

You can definitely remove the MTV (manifold tuning valve) from the top of the engine. From the sounds of your symptoms, it would appear that you definitely have a fuel leak inside the plenum. As I said earlier, the fuel pressure should rise to right around 60psi and should only drop a few psi when the pumps shuts off. If it bleeds all the way to zero, there is a leak in the system.

I would not drive your truck until you get this sorted out.