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I have a Jeep with a transplanted 302 out of a 91 Mustang. The electric fuel pump is in the tank and the tank and pump are brand new. Here's the problem. After it sets over night, when I start it up it wants to chug, chug, chug. It lopes really bad. Now if I turn the key off and on about four times and let the pump build up each time it fires and runs well. Any have any idea why I have to do the 4 cycles and how I might fix it? Someone said my fuel lines were too big. My thought on that is, I don't think so. It seems leak back and loose pressure. I can start it up after it has set for a few hours with no problems. It seems to take 10-12 hours to leak back. Thanks for any input.
My first Question is, it a automatic or manual? (Automatic) You might try to do a fuel pressure test, Pressure should be about 30 to 45 Psi when the key is in the "ON" position.(Engine Running) it should increase by 5 to 10 Psi. If it is within these spec, this should eliminate the fuel system.
My first Question is, it a automatic or manual? (Automatic) You might try to do a fuel pressure test, Pressure should be about 30 to 45 Psi when the key is in the "ON" position.(Engine Running) it should increase by 5 to 10 Psi. If it is within these spec, this should eliminate the fuel system.
It's a manual. I need to find the fuel pressure connection point. This thing has split rails with some fancy fittings and such connecting up the fuel line. It has a Pro Composite manifold that I know nothing of. I will have to research that I guess. I remember on my old stangs seeing a shrader(sp) valve where you could check the fuel pressure. I haven't found it yet on this one. The guy told me it had the stock regulator and seems to have done a pretty good job other than the K&N filter. I lost voltage on the volt meter yesterday. I checked under the hood when I got home and found the K&N had rubbed a hole through the main output wire and I think it was shorting ocassionally as the K&N has a wire screen around it. I fixed that and built a bracket to hold the K&N up over on the fender. Thanks
After it sets over night, when I start it up it wants to chug, chug, chug. It lopes really bad. Now if I turn the key off and on about four times and let the pump build up each time it fires and runs well.
Sounds like the fuel pressure regulator and or the backflow checkvalve.
The checkvalve is on the pump, in the gas tank.
I just fixed a Jeep with very similar behaviour. had to replace both the regulator and the pump. At least the pump is removable without dropping the tank (on my 91 at least).
Sounds like the fuel pressure regulator and or the backflow checkvalve.
The checkvalve is on the pump, in the gas tank.
I just fixed a Jeep with very similar behaviour. had to replace both the regulator and the pump. At least the pump is removable without dropping the tank (on my 91 at least).
Sam
Well, I would have to drop the tank. The bed has been Rhino lined and if there was a plate it's gone now. Oh well I guess the first time I feel like really getting into it I will drop the tank. Thanks
no, I meant that the pump on the Jeep is directly removable from the tank near the rear end without having to pull any plates or drop the tank (like in a mustang)
no, I meant that the pump on the Jeep is directly removable from the tank near the rear end without having to pull any plates or drop the tank (like in a mustang)
Sam
Thanks I'll take a look. On my CJ7 the pump and all are on top of the tank almost in the middle. I will look at this YJ and see if I see it.
Well, I finally got around to buying a new fuel pressure regulator. I had to pick up a part for my car so I went ahead and bought one. I'm not sure when I will get around to installing it but I will let you know the results.
Well, I finally got around to buying a new fuel pressure regulator. I had to pick up a part for my car so I went ahead and bought one. I'm not sure when I will get around to installing it but I will let you know the results.
Well, I couldn't stand it. When I got home last night I replaced the solenoid in my car and that went so fast I started on the 302 in the Jeep. I replaced the fuel pressure gauge to no avail. Still does the same thing, surges when starting up and sometimes when I am just trudging along in a high gear and low RPM. It seems to be related. Memories started coming back from my old 302 HO days and I remembered the IPS. This is the Idle Position Sensor. Not to be confused with TPS (throttle position sensor). I plan to check it out soon as I can check it with a DVM. I had one go out one time and looked in the H manual and it said it needed to read somewhere between 6-10 ohms I think between two of the wires. I will have to look it up again. The EGR valve is connected but has no vacuum connected to it and is plugged. I need to make a plate to block it off completly I guess. Well the saga continues.
Well, I couldn't stand it. When I got home last night I replaced the solenoid in my car and that went so fast I started on the 302 in the Jeep. I replaced the fuel pressure gauge to no avail. Still does the same thing, surges when starting up and sometimes when I am just trudging along in a high gear and low RPM. It seems to be related. Memories started coming back from my old 302 HO days and I remembered the IPS. This is the Idle Position Sensor. Not to be confused with TPS (throttle position sensor). I plan to check it out soon as I can check it with a DVM. I had one go out one time and looked in the H manual and it said it needed to read somewhere between 6-10 ohms I think between two of the wires. I will have to look it up again. The EGR valve is connected but has no vacuum connected to it and is plugged. I need to make a plate to block it off completly I guess. Well the saga continues.
Well I dug out the old 87 T-Bird H manual and did the checks. With the ohm meter it was right in the middle of the spec. I then started the motor and measured the input to the Idle control solenoid. It increased with rpm as it should. I then put 12V across the input to the solenoid and saw it work properly. I guess it could still be the actuator that the solenoid drives. It really surges bad upon first cold start...................