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Fuel starvation on acceleration. HELP


OddTodd
09-14-2006, 01:05 PM
I have a 2001 Chevy Prizm, 1.8L, that idles perfectly but shuts the fuel off when any throttle is applied. I've already replaced the fuel pressure regulator, pcm, o2 sensor, and tested fuel pump. There is no change at all.

rhandwor
09-14-2006, 08:27 PM
Are you getting an oil pressure light or does the gage drop when you gun the engine? Is your gas filter partially plugged. If you can blow thru it good if not replace it. Does the fuel pump shut clear off. Check out the ground wires they might be loose. Check out the air cleaner. Wiggle the wiring harness does the car shut off. Use brake clean or contact cleaner and clean the connections from the fuel pump to the computer. A plugged catalic converter can cause problems if you don't keep your car tuned up. Loosen the bolts and give about 1/2 inch of space if this solves the problem buy a new one. Junk yards aren't allowed to sell these items.
If these items don't help I will give you other ideas.

Blue Bowtie
09-15-2006, 10:18 AM
Does the "Service Engine" light remain lit after the engine is running?

OddTodd
09-18-2006, 12:58 PM
Are you getting an oil pressure light or does the gage drop when you gun the engine? Is your gas filter partially plugged. If you can blow thru it good if not replace it. Does the fuel pump shut clear off. Check out the ground wires they might be loose. Check out the air cleaner. Wiggle the wiring harness does the car shut off. Use brake clean or contact cleaner and clean the connections from the fuel pump to the computer. A plugged catalic converter can cause problems if you don't keep your car tuned up. Loosen the bolts and give about 1/2 inch of space if this solves the problem buy a new one. Junk yards aren't allowed to sell these items.
If these items don't help I will give you other ideas.I have already replaced the fuel filter inside the fuel tank and checked the cat for any blockages. The fuel pressure stays around 50lbs. and there is no oil pressure or check engine lights. The vehicle acts as if the exhaust is blocked, but it isn't. I've already cleaned all connections and there are no gauge fluctuations.

OddTodd
09-18-2006, 01:05 PM
Does the "Service Engine" light remain lit after the engine is running?The service engine light does not stay on and there are no stored current codes. There was a history code for the downstream o2 sensor but I replaced that and it made no change at all.

rhandwor
09-18-2006, 07:22 PM
Did you run it through deep water and plug the intake air line with mud? Is your battery voltage normal a dead cell with a voltage of 8v will definately make a difference. A plugged air filter will cause big problems.
With a timing light do you know how to set base timing? Will the computer advance the timing if you try to gun it. Are the hose connections for the air intake tight with no ducktape. Are all the electrical connections plugged in if you did an engine swap. Did you check for a fuel leak allowing air to be sucked into the engine. Take a small hammer and tap the block by the knock sensor does this effect the engine. Also check if it is plugged in.
Pressure and flow are different a big dent in the gas line will drastically effect flow.
Did you work on the wiring harness and forget to connect a couple of wires.
You didn't replace a timing belt or chain and not it set correctly did you.
Something doesn't sound normal I have a friend who gets into these types of problems frequently and its generally something he has done but not realized what it is.

OddTodd
09-19-2006, 11:21 AM
Did you run it through deep water and plug the intake air line with mud? Is your battery voltage normal a dead cell with a voltage of 8v will definately make a difference. A plugged air filter will cause big problems.
With a timing light do you know how to set base timing? Will the computer advance the timing if you try to gun it. Are the hose connections for the air intake tight with no ducktape. Are all the electrical connections plugged in if you did an engine swap. Did you check for a fuel leak allowing air to be sucked into the engine. Take a small hammer and tap the block by the knock sensor does this effect the engine. Also check if it is plugged in.
Pressure and flow are different a big dent in the gas line will drastically effect flow.
Did you work on the wiring harness and forget to connect a couple of wires.
You didn't replace a timing belt or chain and not it set correctly did you.
Something doesn't sound normal I have a friend who gets into these types of problems frequently and its generally something he has done but not realized what it is.I haven't run through water and the engine was not replaced. All connections are good. I just replaced the fuel rail with the pressure sensor. I't still falls on it's face, but, if I spray starter fluid directly into the throttle body I can throttle the engine and it runs fine until the fluid runs out.:frown:

rhandwor
09-19-2006, 01:30 PM
You are making progress they sell throttle body rebuild kits. They unbolt and if you take them apart and soak them in carburetor cleaner and blow them out. Then reassemble them using new gaskets. Napa sells injector cleaner in pressured cans if you have an injector cleaner. The bottle costs over $15.00 if you don't have a discount number.
I would purchase a new injector at a parts store and pull the throttle body and blow carburetor cleaner through all ports use a new mounting gasket and tighten the bolts under the unit. The only one like this I had major problems with the owner replaced the injectors on a big block suburban with a throttle body with ones from a small V-8. He lost the injectors and bought new ones. I have cleaned a lot of injectors but I have an injector cleaner. A lot of G M had a fuel pressure regulator at the back of the throttle body. You can also replace this item. The advantage of the kit is a diagram showing how everything goes together if you don't have a manual.
I think a new injector at advance would be around $35.00. Uses auto zones carburetor cleaner in a yellow can.
Gumout used to pucker your hands but not anymore.
I think you can get it this trip.
I think I got mixed up on what you said. Unplug the vacuum to the pressure regulator if it is leaking gas or runs much better replace it. Their is a return line to the gas tank use a line clamp or vise grips and pinch off the rubber hose if the engine runs a lot better replace the pressure regulator. I assumed you knew how to do this or I would have said something earlier. With 4 injectors it would be cheaper to pressure clean the injectors. I am assuming one day it ran good the next day it didn't. Also spray around the injector base with carb. cleaner as when replacing the fuel rail the injector o-rings have a tendency to suck air. I always greese them with vasoline as it makes easier to install. I bought a system at a pawn shop for about $20.00 I buy most tools at a flea market or pawn shop. I have observed a mechanic buy a new snap on tool and pawn it the same day for spare money. He never went back very poor money manager. Ebay also has good tool deals but they don't take credit like the tool man.

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