88 FJ62 3FE hard start especially when hot

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OK I could use a little help from the MUD braintrust. About two months ago the fuel pump died. Since I was going out of town I took it to Javier's here in Houston for replacement of the pump. They also replaced the fuel filter. Now there are a couple of new things going on.
1. it's noisy. I can here that fuel pump whirring away in the back. Now there is only a stall mat in the back and no carpet, so no sound damping. But previous to replacement, I could not hear it. Maybe the "Fuel tank cushions" are not in the right place and the sound is transmitting to the rear floor?
2. Now we have starting issues, worse when it's hot. This wagon used to start on the first turnover every time. Now it turns over for a few seconds, and usually requires a little gas to start. Once started it runs OK, but I swear it used to idle a little more smooth.

Where to start?
Fuel Damper? I read the thread about the magical little screw, but haven't looked yet.
TPS? We adjusted this per the manual several months ago. Javier suggested it should be done while hot - not sure how you do that, we removed the throttle body to adjust it before. I don't see anything in the manual about adjusting it while hot.
Fuel pressure regulator?

TIA
 
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My fuel pumps have always been noisy enough to hear when outside the vehicle and near the rear tire. I can barely hear it when you turn the key to on but don't crank.

Are you saying you are hearing it when the car is running? That would be rather unusual.

Hot starts don't rely on the cold start injector so it could be anything at this point.

-TPS
-FPR
-MAF
-02 Sensors
-air filter

At this point you really need to dig into the factory service manual and start measuring resistance values, fuel pressure on the rail etc.

Do you have the FSM's downloaded?
 
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Start with the easy stuff...plugs...condition and gap, fuel filter and air filter. Cap and rotor and wires. Makes sure all are in good condition.

verify base timing. Check valve clearance.

after that make sure your battery cables are in good condition and the grounds are good. Make sure your terminals are clean and tight. I’m assuming your battery is nice and strong.

then I’d start looking at efi components and vacuum leaks. Maybe a leaking fuel pressure regulator etc.
 
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Plugs replaced recently (within a couple of months) and gapped correctly
TPS was checked within a year - is there a way to do this while it is "hot"? I had to remove the TB to check/adjust it last time. difficult to do when hot.
fuel filter is new, was replaced when the fuel pump was replaced.
O2 sensors are new within the last year.
Air filter is relatively new.
New battery within a year. cranks fine.
Checked MAF about 4 months ago but I will check it again.
also found a few months ago that the 'cold fluid sensor' wire wasn't contacting well and that was causing issues so I'll check that again.

for the fuel pump - should it run when the key is turned to 'on" - before cranking?

Looking at the manual (RM080U), in order to check the fuel pressure I need to tie a pressure gage into the connection point between the fuel rail and the cold start injector? per FI-47-48? does anyone have a parts list for the bits required? the manual says SST-09268-45012 - looks like a banjo fitting to a barb might get me to a pressure gage?
 

1911

chupacabra
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Also, the EFI relay is a known weak point for the 3FE (maybe more so in FJ80's than FJ62's?) and will cause hard/non starting, so you might check that. The stock one is too small and overheats easily. Usually this only manifests itself on warm starts, not cold.
 
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Just to close this thread out:
Last week it died on my son while driving. All indications were a fuel issue - it would turn over but not start. Towed it back to the shop that put the new fuel pump in a couple months ago. Turns out a short piece of fuel line that goes from the pump to the hard line had burst so fuel pressure was low (yes it was new hose, supplied with the pump). Since it was all in the tank the fuel was just draining out into the tank through the split piece of hose. Shop put in a new fuel pump and a more sturdy section of hose on warranty. I suspect there was a leak there from early on and the fuel system wasn't building much pressure to start, but had enough fuel flow to run? Maybe that would explain the long start.

Anyway, starts quickly again.

Until something electrical died last night. But that is a story for another thread....
 

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