Fuel ?Restrictor??

[DrDucttape]

There is this plate that mounts to the engine where the manual fuel pump would be, the fuel lines hook into it and it appears to have a small orifice for the fuel to flow through. My first reaction is to bypass this restriction, but Toyota put it there for a good reason right? Or is this just an EPA/Eco-commie thing?

 

[hvyman]

Is a fail safe incase the regulator fails.

If you upgrade the pump by pass it or drill it out.

If stock leave it alone.

Also called the j tube.

 

[DrDucttape]

Ok, great to know. Thank you!

My car has great power till it hits about 4250rpm and it seems to choke off, I upshift and the power is back. Just trying to figure out where the restriction is. I have stock fuel system... I'm running 93 octane fuel... I dunno.

T-

 

[hvyman]

Turbo will fall off around 5500.

 

[jake8790]

Check for clogged cats

 

[DrDucttape]

I'm going to run some injector cleaner through the next tank and see if it improves things. It idles real low and misses alot after 25 mins of driving too, I don't think it is related tho.

 

[DrDucttape]

What's a cat

 

[DrDucttape]

I do wonder if my exhaust is plugged off somewhere tho, I am working on a side exh. that I will install in a couple weeks and the current exh. is all rusted, swiss-cheezed, and decroded.... Maybe its' plugged up with rusty hunks-o-pipe..

 

[peste noire]

cat is short for
catalytic converter.

 

[DrDucttape]

I know thank you. Strangely mine does not have one officer....

 

[peste noire]

yea i didnt know if you were trying to be funny or what but once in a while you meet people who dont know what anything in the car is or is for( not saying thats you though).

so then you shouldnt really be having any exhaout issues.

did you check to see if you still have the oneon the dp? cause if i remember right, the supra has 2.

 

[DrDucttape]

Not a problem, there was nothing there to indicate the humor I have a 3" Megan dp thru a dummy cat into stock ratty exhaust out the back. I'm not sure about the stock dp tho, I haven't seen one. Maybe its my air filter, but its pretty clean.

 

[jetjock]

I'll bet the exhaust doesn't stink either. I wish that myth would die.

 

[DrDucttape]

So, I think I am battling a few different issues here.. I did this horrid thing (according to a few wise folks around here) and disabled my EGR on a hunch that it was causing my Idle problems and drove it back from work approx 40 mins. Usually by 20 mins in, if I get to a red light the car is sputtering, struggling not to die while patiently waiting. This time the sputtering is gone, idle is remarkably smooth and the closest I come to a stall is when I drop the throttle (dashpot problem) the engine recovers from the dip in RPM and sits @ 800RPM, waiting to go.

So obviously the EGR or something connected to it is causing issue with the idle, and I have a faulty dashpot causing it to dip off throttle, but I still have the early power drop off which I think is fuel pressure related. I have a FPR coming this week, so I will update with some actual #'s soonish. I am also going to pressure test the intake piping to make sure that is not contributing to the issues by leaking my boost.

Can a manifold exhaust leak cause the power to drop off like that? I hear exhaust noise under my hood, but I thought it was post turbo since I stripped an elbow bolt installing it... Maybe it is manifold leak, but I thought the sound would have a pop to it, sounds more whistle-y.

T-

 

[jetjock]

EGR flow at idle will indeed cause problems however disabling it and seeing improvement indicates the valve is functional. Since EGR is already disabled at idle by ported vacuum you may want to check if it's plumbed correctly.

 

[DrDucttape]

The vac hoses were plumbed correctly, but I did a test on those little metal vac lines and I think the one that hooks to the EGR VSV was plugged. I tried compressed air and nothing flowed through. Poked some wire in it and sprayed cleaner down there and finally air would go through it. Maybe it will work better this trip. EGR is hooked back up.

I'll report back-
T-

 

[jetjock]

Makes no sense. If the line was plugged the EGR was already disabled so how did you disabling it prior help? And why are you not testing the system per the manual? One of us is corn-fuzed....

 

[DrDucttape]

Manual? What is this thing you call "Manual"?

 

[DrDucttape]

I dunno, but since I screwed with it the idle is good... Didn't get a chance to open it up on the way to work, tough to go 0-80 in rush hour traffic.

 

[DrDucttape]

Ok, so here's the update:

After clearing the blockage in the vac line to the EGR the idle smoothed out but still would dip down and want to stall when I get off the throttle and power would still drop off bad at the 4K rpm area.

Poured in some injector cleaner when I fueled up and after 100 miles driving, now I have no stalling, idle is even, and I have ample power 5K rpm plus.

Yay! Glad the rest of the solution was that simple.

Thank you all for your input!

T-