Its an 88 F-250 4x4 with a 302 EFI 5-speed. Fair compression, runs smooth. When I press the gas pedal it takes about 5 seconds for the old girl to return to idle. I know nothing about EFI. My buddy,s out of town with the hand held mechanic. Is there anything I could check till he gets back.
View 6 RepliesI have a 1988 Ford F-250 Lariat, 7.5L 460, four-wheel drive. I have two fuel tanks on it, and I've been having a really annoying, obnoxious problem with it lately. After running it for a while, I noticed that I keep losing fuel pressure, and the truck stalls. When I try to start it, it does nothing but roll over. It just won't start. I've changed the fuel filter, I know both fuel pumps are working (I turn over the key, I can hear front, back, and high pressure pump attached to the left side frame rail kick in.) It's Fuel Injected, not EFI, hence that third pump. The problem happens a lot, and it's random. I could drive for 100 miles, stop to get something to eat, come out, and it won't start.
I thought maybe it was the fuel pressure regulator, but I don't think that's the case because it still runs. I would assume that if the regulator was bad, it wouldn't run at all. I also thought that maybe it was the relay, but according to some mechanics I spoke too, if I can hear the pumps kick in when I turn the key over, then the relay is fine. The only thing I could think of is that it might be the fuel selector switch. Maybe it's going bad, shorting out or something. When I flip the switch though, it switches between fuel tanks, and the gauge reads how much fuel is in it from the sending unit.
There's a schrader-type valve up by the fuel injectors. When I push it in, it barely squirts any fuel out, if at all, so I know the pressure is low. When I push it in on a good day, it sprays out like a water fountain. Just tried starting it again - no good. Pushed on the valve, it spurted out some fuel pretty well, but still won't start. Occasionally tries to, but ultimately won't. I know the spark is good, checked the plugs/distributor cap. Can't get the sucker to start.
I have a 1988 f-250 with a 460 motor. I have fuel and I have fire. And the truck starts with I prime it. I tried looking for the crank sensor but can't find it. I looked behind the balancer and I didn't feel any wires or anything. I checked on the sides of the motor nothing. It has a new coil pack and ignition mod. Fuel pump and starter. What else can it be?
View 4 Replies1988 F250 351 5.8
I've worked for months on this truck and I now have it in the shop. The truck shows a 41 code and has a lean miss at idle that get worse during acceleration and cruise. The injectors were refurbished 6 months ago and the ECM was replaced 3 months ago. All sensors are new and within specs. Fuel pressure is good and there are no vacuum leaks.
The mechanic has verified that the condition is not electrical related. The O2 sensor will react if carb cleaner is sprayed into the throttle but other wise shows constantly lean. He's now checking all pins at the computer for any off condition. He is suspicious of the refurbished injectors. I'm wondering if the computer somehow went out again. Which way to go or what/how next to test?
cant figur this out have no signal to injectors and no power at fuel pump 88 f150 5-0
View 2 RepliesI have an 88 E350 With a 460 EFI . Problem is there fuel is coming out of the ecs canister . It has the dual canister set up fuel comes out of the rear one after the engine starts. I have never seen this before. What would cause this ?
View 2 RepliesWorking on a 88 Ranger 2.9L 5-speed ext cab. The fuel pressure drops off fairly fast when turned off and I'm pretty sure that the check valve is bad. My question is, which pump has the check valve? It is a single mid tank set-up and has a pump in the tank and on the frame.
Pressure is fine while running. about 30psi @ idle and 40psi with no vacuum on the regulator. The pressure drops off within a couple of minutes which causes it to have to crank over for a bit to rebuild pressure and start.
It looks like the frame pump is readily available while the in take pump is special order. I just need to know which one has a check valve. I'm thinking the in tank pump, but I hate to waste money for the wrong pump.
Pressure drop rate
30 psi @ shut off
25 psi @ 1:05 min
20PSI @ 2:30 min
15psi @ 4:45 min
still dropping
My 88 F150 (300 six, 5 speed, dual tanks, 176,000 miles). The truck has the low pressure fuel pumps in the tanks and the high pressure pump on the frame rail setup. Truck starts fine, but cuts out severely under acceleration for the first 30 seconds of driving. After that I only notice the problem when applying a lot of throttle (does not cut out under gradual acceleration) or climbing steeper hills. If I kill it for a few minutes and then take off again the problem is back for the first 30 seconds or so. I have replaced all the tune-up type stuff (all filters, plugs & wires, dist. cap & rotor, ignition coil, o2 sensor, cleaned throttle body, replaced IAC valve, numerous sensors). Timing is dead on at 10 deg. BTDC with SPOUT unplugged. My FPR was bad so I also replaced that. Condition exists regardless of which fuel tank I am using (no problems with tank selector).
Getting no KOEO codes, but getting KOER code 41 and plugs do seem to show a lean condition possibly. I'm still averaging around 16 MPG since this became a real problem about 3 months ago.
I removed the bowl from the reservoir between the tanks and the high pressure pump on the frame. No filter in there, but it was clean with no gunk or sediment found. I removed the line from the inlet side of the high pressure pump and found that while cranking the engine I have fuel flowing freely (same amount of flow regardless of which tank I've switched to). The flow was steady, but not extremely strong. If I understand right the in-tank pumps are not designed to provide much pressure? Below is what I found at the schrader valve:
key on, engine off - high pressure pumps runs for about 1 second, brings gauge up to 48 psi
idle, FPR connected - 40 psi
idle FPR disconnected - 52 psi
revving throttle with FPR connected - 46 psi maximum
Connector, where fuel pump relay plugs in, seems to be clean and not corroded at all.
I have a '88 F250 with a couple of dual tank issues, first of all if I'm running on the rear tank the fuel returns in the front tank.... not an isssue if trhe front tank is empty, but if both tanks are full the front tank will overflow. If the front tank is empty I run on the back tank until I'm out of gas and switch to the front and I"ll have about a half a tank in the front tank.
Second issue, running the front tank the fuel gauge stays on full until I have about half a tank, then it works OK. If I'm running the back tank it stays on full, even after the tank runs out of gas??
i recently got a 86 f250 351w ho. My problem is when i go from a stop or even slow for a turn then reaccelerate it bogs down and i have to pump the pedal to keep is going. My first thought was the accelerator pump but now I'm thinking power valve? I believe this carb is a Holley 4180?
View 3 RepliesI just bought another 1991 Ford. This one is a 1/2 ton XLT Lariet with the 302 and for the first time I own a short bed. I also have a 1991 F-250 XLT with a 460 and a 8' bed.
Here is the problem, ( I think) it will not run or at least not for long. The fuel pump, which I am guessing is in the rear tank will not stop running. On the F-250 the pump stops running after a few seconds after I turn on the key.
Where should I start to find out my problem with the fuel system?
My F250 heavy duty isnt getting voltage to the fuel pump relay.....
View 2 RepliesI have a 94 F250 5.8 liter with 96K miles. Can I remove the fuel rail and clean or replace the filter that is placed at the top of the fuel injector?
View 10 RepliesI have a 77 f-250 with a 460 engine and a 4bbl Motorcraft carb and its leaking a substantial amount of fuel out of the newly replaced filter that is attached to the carburetor. The fitting is tight and I even tried buying some small gaskets to seat it, but that didn't work either.
View 1 RepliesI have an '88 EXP Escort with the non-HO 1.9L
I was noticing a rough idle (vibrating, sounded like it was bogging down)
I changed the plugs, wires, cap and rotor. Still happening.
Noticed that my o2 sensor was unplugged. Plugged it back in. Still happening.
Went to check the air filter and noticed the insane amount of fuel that was coming from my injector.
I am getting horrible gas mileage (8-12mpg)
Here is a video of what I am seeing: [URL] ....
What would be causing that much fuel to be sent out?
I am a newbie as far as fuel injection. The original issue the truck had was no fuel. I tracked down the issues to a blown fuel pump relay and a melted inertia switch. I jumped the inertia wires with a new fuel pump relay installed and the truck ran at an idle and up to 3500 RPM when stationary. If the truck is going up a grade or needs more throttle it will start to lose fuel pressure and end up stalling. I had the fuel pressure gauge connected to the schrader valve on the fuel rail and had 30-35 PSI when idling. It runs good under light load on the throttle.
Under heavy load it starts to drop quickly and if you back off the throttle it will stay running some times. I changed the fuel filter and also replaced the high pressure pump on the main frame and it still has the same problems.The original pump was pumping about 13 ounces of fuel in the 20 second test that the repair manual suggested. I have even placed a jumper wire direct to the new fuel pump to bypass original wiring and possible problems. When it stalls under load (No Fuel pressure) at the schrader valve you can hear the fuel pump running but there is no fuel pressure.
If I turn off the ignition for a few minutes and then turn the key back to the on position it will start to pressurize and then start and run at an idle. I even replace the ignition switch as it was a little temperamental. I have not changed or checked the fuel pressure regulator as it is a pain to get to at the back of the engine. I do not want to spend a fortune tracking down this problem since the truck may not even pass its smog inspection and may be a parts truck only.
67 F-250 4x4
73 Crew 4x2 (4x4 Soon)
89 F-250 Super Cab 4x4
1991 F150XLT, 5.0, E4OD....Should the EFI system bump up the idle speed when the AC system is operating to compensate for the compressor load? Obviously I'm asking because mine sure doesn't. With AC on, the idle speed will drop to around 300rpm in Drive, like when sitting at a red light for example. Surely this isn't normal operation...is it?
View 4 RepliesI have a 4160 on a 351 Ford. I confess, it's a boat!
I had a major flat spot when accelerating off idle. I found it wasn't pumping on the accelerator circuit.
I replaced the accelerator diaphragm and cleaned the squirts and the passages. It squirts great now, but if I floor it, it completely bogs. If I baby it really carefully, once the engine gets over about 1800 rpms, it acts fine.
I thought it over, checked the travel on the arm that presses the diaphragm, and figured my pump cam was worn. It "seemed" like the duration of the squirt was not long enough.
I got a new cam kit. The orange cam on my carb was not a bit worn compared to the cam in the kit. Not encouraging. I put the only other cam in the kit that I thought might work. It was blue, and it gave more lift but no greater duration. It did not make any difference that I can tell. Is there a transition circuit I might have problem with? I don't know enough to go any further.
I rebuilt a 1963 ford 2B crburetor with manual choke. Put the carburetor on and it runs very rough. Won't go below 800 rpm or it dies and I need to choke it to start. Thought it was a vacumn leak so sprayed WD -40 and no change in idle. So pulled off the carburetor and put on the previous carburetor (with electric choke) and it runs great. I want to use the manual choke to hook up the cable though. I replaced everything in the carb. What do you think it is?
View 5 RepliesI picked up a 90 f150 with the 302. it wont idle without a little throttle, so after a quick look under the hood i noticed alot of broken torn and missing vacuum lines. Where I can get some sort of diagram for routing?
View 1 Repliesi have a 78' F-250 4x4 4 speed with a straight 6. it has headers and an eldebrock 600 on an offenhouser dual plane intake. The carb just randomly started acting up the other day and what to try now. it will sputter and just about die when i first let off the clutch then it will suddenly start racin. its really annoying and hard to drive. i checked the inline fuel filter and it should be getting plenty of gas. didn't find any vacuum leaks.
View 14 Replies