Altered Mental Status (1G AWD 5spd)

[Anfurnyy]

Did that have a return line?

It did

 

[CrackedDSM]

Pressure stays at 41-43 after key is turned off. Takes a solid while to fully bleed down.


I think honestly I'm motivated AF to start over on the tune. I'm gonna keep these settings(duh) just in case, but with the MAFComp adjustments I know where in the VE map to pull and roughly how much. It's worth a try even though I'm sure it'll be a slow process.


Probably start tomorrow now that my clevis came in. This thing was kind of brutalized though, so we'll see how installing that goes...


But plan for tomorrow is try to install this new modified clevis, and start over on the tune. Use deadtimes to get car idling at the proper Wideband/AFR est matching, then adjust VE to see if I can get it driving.

 

[CrackedDSM]

What size is the o-ring for the fuel pump? Downright infuriating that I cannot find this information on the internet everywhere. Every single thread that has this in the title ends with "just buy the walbro install kit" or "use this toyota spacer".

Dealerships are all closed on Sundays and I'm not spending $20 for a single o-ring.


Edit - honestly, screw it. I’ll just cut the bell off and use the hose and clamps the kit came with and delete the o-ring entirely.

 

[Stapl3]

Just cut off the cone and do it as pictured here.

 

[Justin DuBois]

Pressure stays at 41-43 after key is turned off. Takes a solid while to fully bleed down.


I think honestly I'm motivated AF to start over on the tune. I'm gonna keep these settings(duh) just in case, but with the MAFComp adjustments I know where in the VE map to pull and roughly how much. It's worth a try even though I'm sure it'll be a slow process.


Probably start tomorrow now that my clevis came in. This thing was kind of brutalized though, so we'll see how installing that goes...


But plan for tomorrow is try to install this new modified clevis, and start over on the tune. Use deadtimes to get car idling at the proper Wideband/AFR est matching, then adjust VE to see if I can get it driving.

Thats great!, then there is no issue with the o-ring. Key on prime should not need to be very long.

 

[CrackedDSM]

Thats great!, then there is no issue with the o-ring. Key on prime should not need to be very long.

Why do you think it’s acting like it’s got air in the line? It’s so hard to start when hot, and it’s only changed with the fuel pump replacement. I didn’t replace the o ring with a new one.


Fuel pressure remains constant and doesn’t dip when it dies and when cranking it and it doesn’t start, fuel pressure is perfect at 41+. But several primes of the key/pump fixes it and it starts.


I just don’t get it. I might tinker with it more tomorrow and try to record the Fuel pressure gauge when it’s doing it. Try to repeat the result tomorrow.


Might pull the o2 sensor too and see if I can clean it or something. Please help guys. Give me some diagnostic things to test and do to see what it might be. I’m gonna try the narrowband simulation thing again tomorrow and see if that makes a repeatable difference.

 

[Justin DuBois]

Hard start when hot isn't one I've had myself. I'm wondering if it floods, or is starved... When its happening, I'd disconnect the injector wires, and crank. If it tries to start - you were flooded.

 

[1990TSIAWDTALON]

Is "Key Start" working when it's hot. That's the only time I had trouble getting my car to start. It's very important. @steve helped me figure that out, and thank God. It was almost impossible to get to start when it was hot and it wasn't working. I can't remember what he proposed, but whatever it was, it cured the hot start issue. It's been a while since we dealt with that. Log it and you can see it change from "0" to "1" on your cold starts. It should remain the same during hot starts.

 

[Dericsh]

Did you try disabling hot start enrichment? Maybe it’s not needed with the new pump.

 

[CrackedDSM]

Did you try disabling hot start enrichment? Maybe it’s not needed with the new pump.

I’ll try. I’ll do anything before I have to cut up a sending unit.


Not sure why this problem is happening. The only thing I can think of is the oring seals a little but not entirely. So it’s not as bad as a super leaky oring but just a little off kilter.

Idk. I’m reaching. We’ll see though.

 

[Anfurnyy]

What size is the o-ring for the fuel pump? Downright infuriating that I cannot find this information on the internet everywhere. Every single thread that has this in the title ends with "just buy the walbro install kit" or "use this toyota spacer".

I just checked my 2 walbro install kits and I didn't see any o-rings in there at all. Bought both kits for the dual 450s I have in there now. Unless there's a DSM specific one somewhere.

I vaguely remember a video of some sort about o-rings on the fuel pump, did jafro make one?

 

[CrackedDSM]

Modified the fuel sending unit to just do a rubber hose and clamps.


Now it bleeds down pressure immediately to 0 after engine is turned off and is generally idling even worse.

Gonna take the sending unit out again and make sure the clamps are tight but this is f*cking infuriating I assure you.

 

[CrackedDSM]

 

[CrackedDSM]

Not sure if this is relevant, but I took the sending unit out and if I blow through the feed hose back into the pump, fuel comes out the sock.


Bad pump? Normal operation?



After searching, others have this issue too. I’m gonna replace the hose clamp that’s suspect, and if it still does it I’m returning this pump and getting a hellcat pump.

 

[1990TSIAWDTALON]

I run the 525 unit WITH the check valve. It still bleeds down but not immediately. It's kinda normal for the pressure to drop. Some days, it will not drop for a hour, other days it drops in a minute or 5.

 

[CrackedDSM]

Update: I swear to God the clamp was tight, but after going to parts store and getting actual fuel line clamps(it's like a mini-tbolt clamp), I tightened the JESUS out of it and no more issues. Starts up fine, idles great, doesn't die after 30 seconds. Fuel pressure stays rock steady after ignition cut off with no signs of bleeding down.


I'll test later the hot start issue, but for now..I'm just gonna take my win. Now I know for sure the seal between the pump, and the sending unit is solid AF. Any issues from here is something else.

 

[Justin DuBois]

Update: I swear to God the clamp was tight, but after going to parts store and getting actual fuel line clamps(it's like a mini-tbolt clamp), I tightened the JESUS out of it and no more issues. Starts up fine, idles great, doesn't die after 30 seconds. Fuel pressure stays rock steady after ignition cut off with no signs of bleeding down.


I'll test later the hot start issue, but for now..I'm just gonna take my win. Now I know for sure the seal between the pump, and the sending unit is solid AF. Any issues from here is something else.

I love the fuel line hose clamps - I use them lots of places.

 

[curt-s]

Well, now you've got me wondering.. I use -6 bulkheads, so no o-ring, but worm clamps on both sides of the hose (https://www.dsmtuners.com/threads/the-other-wife.540835/post-153909622)

Doesn't hurt to try, I guess. Next year . 1 day left of double digit weather.

 

[CrackedDSM]

This thing is still an absolute nightmare to start when it's hot. It doesn't die, most of the time, but yeah. I think Justin is right and it's just really rich. If I let it sit for a few seconds, like 15+, it'll start. If I try to start it immediately, it will just crank and crank and crank and crank.

Next thing I'm gonna do is send these injectors off to get cleaned and flowed and hope it's not a waste of $125 + shipping. I think I'm gonna replace the AFPR's diaphragm at the same time, because it's running 40-41 at idle. Even with only -6/-8 vacuum at idle, it should still be in the 30's. Not 40's. With the vacuum line plugged, it's 43.5. Weird.


Also: I need a favor from any of you 1G M/T guys. Do this for me:

Put the car in neutral. Rev and hold it to 2K. Clutch in and try instantly to put it into 1st. What happens? Does it go right in? If it grinds, how long does it take for you to be able to put it into first? Count your mississippi's for me, please. Gonna make a separate thread too, because I'm curious.

 

[Justin DuBois]

This thing is still an absolute nightmare to start when it's hot. It doesn't die, most of the time, but yeah. I think Justin is right and it's just really rich. If I let it sit for a few seconds, like 15+, it'll start. If I try to start it immediately, it will just crank and crank and crank and crank.

Next thing I'm gonna do is send these injectors off to get cleaned and flowed and hope it's not a waste of $125 + shipping. I think I'm gonna replace the AFPR's diaphragm at the same time, because it's running 40-41 at idle. Even with only -6/-8 vacuum at idle, it should still be in the 30's. Not 40's. With the vacuum line plugged, it's 43.5. Weird.


Also: I need a favor from any of you 1G M/T guys. Do this for me:

Put the car in neutral. Rev and hold it to 2K. Clutch in and try instantly to put it into 1st. What happens? Does it go right in? If it grinds, how long does it take for you to be able to put it into first? Count your mississippi's for me, please. Gonna make a separate thread too, because I'm curious.

If you manually pull a vacuum on the AFPR, do you see PSI below 40psi while the pump is running? When I upgraded my fuel pump I had to address a stock FPR overrun and then some back pressure issues from the return line.

 

[CrackedDSM]

If you manually pull a vacuum on the AFPR, do you see PSI below 40psi while the pump is running? When I upgraded my fuel pump I had to address a stock FPR overrun and then some back pressure issues from the return line.

I am not sure I have the capability to pull a manual vacuum on the AFPR. How did you do it? You've got me curious now, as that's a fantastic test before I pull the trigger on a diaphragm.

 

[curt-s]

Suck, boy, suck

 

[Justin DuBois]

I am not sure I have the capability to pull a manual vacuum on the AFPR. How did you do it? You've got me curious now, as that's a fantastic test before I pull the trigger on a diaphragm.

I have a hand pump, which I normally use with a brake fluid reservoir for bleeding hydraulic lines.

 

[CrackedDSM]

I had have a hand pump, which I normally use with a brake fluid reservoir for bleeding hydraulic lines.

Oh!! I've got one of those as well, I didn't even THINK of that. God that's a good idea.

Suck, boy, suck

I just don't have the lung power to do it.

 

[Anfurnyy]

If you manually pull a vacuum on the AFPR, do you see PSI below 40psi while the pump is running? When I upgraded my fuel pump I had to address a stock FPR overrun and then some back pressure issues from the return line.

I can't imagine his overrunning that aftermarket regulator and the return with a 320lph pump

I HAVE heard of this though.