1HD-T Injection pump options

[foxtrot678]

hey everyone, I have a 1993 1HD-T with a manual transmission. I’m having an issue where when I go up hills, and break at the same time, my engine will stall out when pulling up to a stoplight. It also has the same problem when making a sharp left turn, bogs out with no acceleration even with the pedal to the floor (seems no fuel). it has also been harder and harder to start it (used to start right up but takes 3-5 seconds of cranking now). in the situations where it stalls, it takes 10 seconds of cranking to get it started again.

only thing i can assume is some internal springs are worn and ready for replacement. engine has 575,000km on it so no surprise there, not sure of previous rebuilds. i’ve done extensive searching and reading through old threads on this topic as it seems to have been a problem before, but no real final solution ever comes up. so my questions for the group:

should i just move forward with a rebuild of the pump and injectors? looking at making more power in the future, so could upgrade the pump at the same time.

any reliable shops that can rebuild a denso pump and injectors here in the US? looked at the shop in Oregon that has been mentioned on here, but the have a 3-4 week turn around time; which means i’m 5-6 weeks of downtime on my daily driver.

i’m also looking for exchange options so i can minimize downtime but everyone seems to be out of stock.

pump info:

• Toyota PN: 22100-17540
• Denso code: 754

thanks for the help!

 

[Squash]

First off, make certain that the pump is not sucking air. Easy to figure out because your primer will be soft until you pump a few times. Primer should stay firm, or firm in a couple pumps is sitting overnight.
Did you delete the ACSD?
If this thing fails....shavings will enter the system via the screen under the fuel solenoid which starves the pump of fuel.
With your mileage, if the above are fine then a teardown might be appropriate.

 

[foxtrot678]

First off, make certain that the pump is not sucking air. Easy to figure out because your primer will be soft until you pump a few times. Primer should stay firm, or firm in a couple pumps is sitting overnight.
Did you delete the ACSD?
If this thing fails....shavings will enter the system via the screen under the fuel solenoid which starves the pump of fuel.
With your mileage, if the above are fine then a teardown might be appropriate.

sorry, should have stated all the work done so far.

- deleted ACSD
- replaced all rubber lines at tank, between hard line and filter housing, and between filter housing and pump
- replaced filter housing with new OEM without fuel heater
- replaced fuel filter with OEM
- replaced water level sensor on the bottom of fuel filter
- cleaned pickup screen in tank

 

[rick_d]

Bleed the system again. While running crack the injectors. repeat.

Sounds like an air leak.

There is ZERO reason to use a US rebuilder for pump if you are in Deutschland. It is a denso pump and there must be a decent amount of people who can manage that job in neighborhood.

 

[foxtrot678]

I never updated my location apparently, i’m in Arizona

 

[foxtrot678]

also, this has been going on for about 3-4 months. i’ve bled the lines a few times. when it starts to die when going up hill, i am able to save it by feathering the throttle and it doesn’t die. it’s like when it returns to idle from a higher RPM, it just continues down to zero

 

[Squash]

The system is under vaccum!
Somewhere/something is allowing air in.
You won't see this, might hear it if you listen in a quiet place.
The old clear hose trick works like a charm.
Start at the pump to filter and work upstream towards the tank.

 

[foxtrot678]

definitely air in the system, just put a clear hose on and there is barely fuel trickling through the hose (10% fuel and 90% air)

was going to bleed the high side, but there doesn’t seem to be any air getting in the high side. what’s the best way to bleed between the primer and the pump? i don’t see any type of bleed screw on the pump.

tried removing the glow plugs but a couple of them seem to be stuck and i’m not gonna snap one off trying to do it this way

 

[foxtrot678]

well… think i finally figured it out. thanks @Squash for the idea at the air again. i had moved on from that idea since i had replaced everything down line. the clear tubing showed a an obvious air leak. there were bubbles on both sides of the primer, indicating it was leaking in further back. got the fuel pickup hatch opened up and i had reused a spring clamp on the new rubber line (was one worm clamp short at the time) so i replaced with a worm clamp and no more bubbles! crazy how something so simple can cause so many issues. it was holding enough pressure on the rubber line to not let any fuel by but was sucking air when running. haven’t done long term road tests yet but it seems to run much better, and no bubbles.

 

[Themcfarland]

Thanks for following up. It will help everyone

 

[foxtrot678]

following up again on this. Seems I still have a leak somewhere that is letting air in, and I lose prime when it sits for more than a couple hours. I’ve torn it apart to test the filter assembly in different assemblies for leakage. The only leak I have found so far is in one of the return lines where it bolts to the injector. The crush washer had a slight leak in it.

What I don’t understand and what my main question is is how the return line order of operations works. What prevents the injection pump from sucking fuel through the return line or arrogating into the injection pump from the return line while it’s sitting? If it was just that crush washer that was leaking, how is the air getting back to the feed line from the return line side? Is there a check valve or something that prevents fuel from flowing backwards through the return line?

I took the banjo bolt off for the return line and could not see any kind of springs or anything inside. Look through the manuals, but nothing really specifies how to return line works if anyone can help out with some knowledge on how it operates that would be great so I can check everything thanks

 

[rick_d]

Your delivery line is issue not the return. I can reprime my fuel filter housing in about 5-7 pumps after a few days but just to top off prime. I use solid wide clamps (fuel injection style) at all metal to rubber connections. 10mm supply lines in 80 series are a problem and have been solved by inline walbro electric pumps (near tank). You could also upsize to 12mm (or 12.7mm Ala 1/2") metal and rubber from tank to ink pump. There is a Porsche rubber hose supplier in Flagstaff who can get you the rubber. 23811-17060 Is the long ink pump hardline if you have something else. Photos will help.

 

[foxtrot678]

i do already have the 12mm lines. i’ve replaced all rubber lines and new worm clamps for the entire feed side. i’ve also replaced the filter assembly with new oem, and even tried a racor filter system to rule out this as the culprit. clear lines from firewall to filter have no air, but line after filter has air in it. bypassed filter assembly straight to pump, and air is present in the system. replaced crush washers at the pump inlet pipe and outlet, but still air is present. only thing i can think at this point would be the pump itself then

 

[foxtrot678]

A little Monday update. after putting the clear lines back on, i noticed something. i made sure all clamps were as tight as possible to eliminate any air leaks, and after sitting overnight, the clear hoses were collapsed, but with no air in them. the clear tubing had a much thinner wall than the black rubber, so it was easier to collapse, showing that there was a vacuum in the system. took the fuel cap off and it hissed and hoses went back to normal.

i took the gas cap apart and cleaned it out as it was pretty cruddy, and we will see what happens now.

what i assume was happening, is the filter on the gas cap was clogged, so as i drive and used fuel, it was not letting any air in and creating a vacuum, which drew the fuel back into the tank after sitting for a few hours. hopefully this works!