I'd be willing to bet the noise is the diaphragm vibrating in the FPR under pressure.
Hard Start: Fuel Pressure Loss at Engine Shutdown (1 Viewer)
- Thread starter DesertCruiser80
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- 1992 3fe hard start
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plausible
- Thread starter
- #43
I'm in the process of removing everything between me and the injectors. Having a hard time removing the intake manifold. Yes, I'm using the FSM (page FI-57). Figured I'd ask in this thread instead of making a new one.
I've removed the connectors, hoses, EGR stuff, cold start injector pipe, the 2 bolts holding the stays in front and behind the manifold, 2 nuts and 7 bolts at the bottom of the manifold. The thing will not move. The mechanic I took it to previously decided to put a silicone gasket on the mating surface at the bottom. Could that be holding it? I gave a couple good tugs and it didn't release.
I've removed the connectors, hoses, EGR stuff, cold start injector pipe, the 2 bolts holding the stays in front and behind the manifold, 2 nuts and 7 bolts at the bottom of the manifold. The thing will not move. The mechanic I took it to previously decided to put a silicone gasket on the mating surface at the bottom. Could that be holding it? I gave a couple good tugs and it didn't release.
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confirm that you've remove all the nuts and bolts
use a rubber mallet and hit it like you mean it
or find a place where you can use a long flathead screwdriver as a leverThe silicone gasket does indeed do that. It'll be tough to nudge but itll come out easily when it does
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- #45
I was finally able to pry the intake manifold off. For the record and those who might have the same problem later on, the solution was to use a gooseneck crow bar. The ones that curve back towards you. I found the best location to place it was between the air/smog pump and the manifold. My manifold had a nub that sat above the mating surface that I could grab a hold off. Needed to take off the air tube from the filter to the pump. Pry towards the front of the vehicle.
As for the repair, I'll get at the injectors this week then have them cleaned.
As for the repair, I'll get at the injectors this week then have them cleaned.
test the injectors first, if they are leaking don't bother cleaning them
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- #47
Update: Injectors have been serviced and on the way home. Tech reported a pre-service flow difference of 9% between least and greatest volume. Post-service difference is nominal. No leak was reported by tech. Will report back when injectors are installed and car is running.
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- #48
I am currently installing the injectors and fuel rail and have a question. I am torqueing down the rail, but noticed the injector boots (if thats the correct name) seem very compressed and mis-shapen. Current torque is about 8 ft-lbs, 1 ft-lb short of spec. Have I tightened too much already or is this okay?
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- Thread starter
- #49
Looking through pictures of other 3FE injectors, I noticed mine stick out from the manifold a good bit compared to others. This pic was from tucker74 in the thread "3FE adventure". My injectors came back with a rubber spacer on the pintle cap, but I did not send them in with one. I think that is what is causing the spacing issue. I'll take them off.
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- #50
I need to not be so mechanical and think when doing things. When the injectors were initially removed, the rubber spacer stayed in the injector cup. I doubled up when I went to install refurbished injectors. Hence the issue. Ordered new cups+orings. The old ones were nasty. Thanks for the rubber ducking MUD!
I'm about at the point of doing the fuel injection on my rebuild, so this and the diagnostic info, is timely.
Do you happen to have a pic of the end of your injectors? I'm curious which style they are.
Do you happen to have a pic of the end of your injectors? I'm curious which style they are.
best of luck.. happens to all of us :dI need to not be so mechanical and think when doing things. When the injectors were initially removed, the rubber spacer stayed in the injector cup. I doubled up when I went to install refurbished injectors. Hence the issue. Ordered new cups+orings. The old ones were nasty. Thanks for the rubber ducking MUD!
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- #53
Sweet, thanks. I'm more curious than anything else, because I have both kinds. I've got a '90 date (91 model year) motor and a 91/91 motor, and the injectors are different between them.
- Thread starter
- #56
Gents, I have a car again! After re-assembly, she is running, although not perfectly (more on that later).
Starting from where I last left off: Installation of injectors. I had a hard time installing the injectors properly. Reason being the pintle caps of the injectors would never fully enter the plastic spacers on the engine. Solution: Assemble the injectors+spacers first, then install the injectors on the fuel pipe, THEN install pipe onto engine.
Next up, manifold installation, where I stripped a bolt. Turns out, the intake manifold bolts are NLA. The kind sir at my dealer found that 22R manifold bolts are almost identical. Difference is 22R bolts are grade 5 vs stainless steel and they come with a lock washer. Threw those on, and the rest was relatively painless.
It took 4 cranks, but she finally caught. I noticed a high idle, ~1100 rpm. When I threw it in gear, the truck wanted to really move without my foot being on the pedal. My guess is I have the accelerator cable too tight at the throttle body. I'll loosen it and check. As for the original issue of hard starts, I will monitor as I start driving more frequently.
Questions welcome, cheers
Starting from where I last left off: Installation of injectors. I had a hard time installing the injectors properly. Reason being the pintle caps of the injectors would never fully enter the plastic spacers on the engine. Solution: Assemble the injectors+spacers first, then install the injectors on the fuel pipe, THEN install pipe onto engine.
Next up, manifold installation, where I stripped a bolt. Turns out, the intake manifold bolts are NLA. The kind sir at my dealer found that 22R manifold bolts are almost identical. Difference is 22R bolts are grade 5 vs stainless steel and they come with a lock washer. Threw those on, and the rest was relatively painless.
It took 4 cranks, but she finally caught. I noticed a high idle, ~1100 rpm. When I threw it in gear, the truck wanted to really move without my foot being on the pedal. My guess is I have the accelerator cable too tight at the throttle body. I'll loosen it and check. As for the original issue of hard starts, I will monitor as I start driving more frequently.
Questions welcome, cheers
- Thread starter
- #57
After some drives around town, truck feels great. The high idle was solved by loosening the accelerator cable and I further tightened the kickdown cable. Shifts were too "floaty" and luxurious. Feel snappier now. Main benefit I see/feel from the injector cleaning is power and balance.
Regarding the original issue of hard starts, it seems to still be there. I've had some hard "choked" starts, but I believe those were caused by me not leaving the key turned long enough to fully turn over the engine. The hard starts now are characterized by long cranks. I say long in a relative sense, very subjective.
Today I started the truck twice: cold and hot, with about 40 mins in between starts. Both times, engine cranked for long enough to normally start. I backed off, then tried again. Engine fired up in less than a second the 2nd attempt.
Next tasks: Verify fuel pressure is holding after engine shutdown, valve adjustment, and verify proper timing setting. I will start timing my cranks and report them.
Regarding the original issue of hard starts, it seems to still be there. I've had some hard "choked" starts, but I believe those were caused by me not leaving the key turned long enough to fully turn over the engine. The hard starts now are characterized by long cranks. I say long in a relative sense, very subjective.
Today I started the truck twice: cold and hot, with about 40 mins in between starts. Both times, engine cranked for long enough to normally start. I backed off, then tried again. Engine fired up in less than a second the 2nd attempt.
Next tasks: Verify fuel pressure is holding after engine shutdown, valve adjustment, and verify proper timing setting. I will start timing my cranks and report them.
- Thread starter
- #58
Finally got a chance to post an update 2+months later. I went on a road trip right after getting the truck running again and timed some start ups, mostly warm starts right after fueling up. Average time was about 2-3 seconds of cranking before starting (stumbling or not). Fastest was 1.5 sec, longest was almost 5 sec. I did notice that it tended to not stumble when tank was full so I thought the charcoal canister was shot. I was having gas vapors spew out when I took off the cap. Swapped that out with a VC120, but did not remedy the problem.
Truck is in the shop now for a proper valve adjust, timing check, and fan clutch replacement as it would not lockup (got really warm, almost overheated on I-5 Grapevine). Mechanic said valve adjust would not affect start but it needed to be done anyhow.
I did manage to record the stumbling start. Once I let go of the key, I let the engine do its thing. I do not press the gas pedal. Video here:
Truck is in the shop now for a proper valve adjust, timing check, and fan clutch replacement as it would not lockup (got really warm, almost overheated on I-5 Grapevine). Mechanic said valve adjust would not affect start but it needed to be done anyhow.
I did manage to record the stumbling start. Once I let go of the key, I let the engine do its thing. I do not press the gas pedal. Video here:
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- Thread starter
- #59
Got around to tackling this annoying startup issue again. Truck was in the shop getting some good good upgrades done. Had the valves adjusted and timing checked. Timing was spot on and valve adjustment was minor. Engine sounds great with a little less tick sound. But starting issue remains.
I tested the fuel pressure again today, as I never did so since rebuilding the injectors. Shop said they observed no leaks when rebuilding.
Pressure at idle = 36 psi.
Pressure with fuel regulator vacuum disconnected = 44 psi.
Pressure seconds after turning engine off = 14 psi and dropping to about 5 psi in less than a minute.
Based on this, I think the only possible cause of this is a faulty check valve in my *new* denso pump. Am I correct in this diagnosis? If so, is there a way to fix the valve without getting a new pump?
I tested the fuel pressure again today, as I never did so since rebuilding the injectors. Shop said they observed no leaks when rebuilding.
Pressure at idle = 36 psi.
Pressure with fuel regulator vacuum disconnected = 44 psi.
Pressure seconds after turning engine off = 14 psi and dropping to about 5 psi in less than a minute.
Based on this, I think the only possible cause of this is a faulty check valve in my *new* denso pump. Am I correct in this diagnosis? If so, is there a way to fix the valve without getting a new pump?
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you can temporarily install a non return valve on the main fuel supply line.
it'll just be easier to install a new pump though
