Knock

[jdanna]

OK i just went out and looked again - at idle, with the vac line on or off the fuel pressure stays around 38psi.
give it a bit of gas it drops a tiny bit. give it a bit more gas and get into the boost it goes to around 40ish.

Since its having knock i wasn't about to give it full throttle.

I just realized the regulator is after tge pressure gauge. Soi dont think changing the vacuum would effect it

 

[jdanna]

I just realized the regulator is after tge pressure gauge. Soi dont think changing the vacuum would effect it

I talked to a buddy of mine and his theory is that with the modifications done to this car - i shouldn't be running stock ignition coils.
I'm going to order the accell ignition pack and install that and see if it helps.

also :
https://lh4.googleusercontent.com/-.../aCJgYCP1IR0/s800/2012-05-20_18-46-32_113.jpg

What is that sensor? and why does it have a disconnected vacuum line?

 

[TurboBuRick]

Fuel pressure is not moving when you remove the vac/boost line? Does the line have vacuum?

 

[mearly65]

Fuel pressure is not moving when you remove the vac/boost line? Does the line have vacuum?

x2. I had the same problem before. When I took the rubber vacuum line off the steel line that goes to the vac port I noticed that the steel line was rusted completely shut. Never had any indication on the outside of the steel line. I temporarily ran new rubber line to the vac port and problem solved. That picture is of your wastegate solenoid. The short rubber hose is not supposed to be there. It should have a small foam filter on it.

 

[jdanna]

Fuel pressure is not moving when you remove the vac/boost line? Does the line have vacuum?

i think the fuel pressure gauge is before the regulator, so it wouldn't be able to register any change.
Just ordered that filter for the solenoid, and the accell ignition pack.

Chip and scanmaster are next.

 

[EYE-OPENER]

My gn had the same exact issue. As I drove it had steady pressure. When I slightly accelerated the pressure would drop a few lbs and as I pressed more it would creep up and would go up on boost quickly. I tried testing it again and pop went the hg. I got it back to the house and dropped the filter as I wasn't sure why I had a drop in pressure. It was full of junk. I dropped the tank and it had crap in it too. So I replaced the tank filter, and both pumps as its a double pumper set up. It fixed the problem 100% and it doesn't take but a few minutes to drop the filter.

 

[TurboBuRick]

i think the fuel pressure gauge is before the regulator, so it wouldn't be able to register any change.

OK

 

[jdanna]

My gn had the same exact issue. As I drove it had steady pressure. When I slightly accelerated the pressure would drop a few lbs and as I pressed more it would creep up and would go up on boost quickly. I tried testing it again and pop went the hg. I got it back to the house and dropped the filter as I wasn't sure why I had a drop in pressure. It was full of junk. I dropped the tank and it had crap in it too. So I replaced the tank filter, and both pumps as its a double pumper set up. It fixed the problem 100% and it doesn't take but a few minutes to drop the filter.

interesting...

Ill definitely check the fuel filter. I doubt the pumps have a problem since the tank looks pretty much brand new, but the filter is easy enough to check.

Tho i did end up with a face full of gas changing a fuel filter on a cadillac once...

 

[aminga]

i think the fuel pressure gauge is before the regulator, so it wouldn't be able to register any change.
Just ordered that filter for the solenoid, and the accell ignition pack.

Chip and scanmaster are next.

On a stock TR the regulator is in the return line

 

[jdanna]

On a stock TR the regulator is in the return line

you see - this is why im here. I had no idea - i was thinking of it as a much more linear system.

Still lots to learn. So the fuel filter could definitely effect both my pressure readings and the proper functionality of the regulator.

 

[jdanna]

Hey - Stupid question -

Whats the best way to change the fuel filter? Should i buy just a filter and replace it, or replace the whole canister?

Is there a way to empty the line before i take it off as to not get sprayed with gas? I was thinking of pulling the fuse for the pump and cranking the starter a few times... Is that safe to do?

 

[EYE-OPENER]

Hey - Stupid question -

Whats the best way to change the fuel filter? Should i buy just a filter and replace it, or replace the whole canister?

Is there a way to empty the line before i take it off as to not get sprayed with gas? I was thinking of pulling the fuse for the pump and cranking the starter a few times... Is that safe to do?

I usually pull the fuse for the fuel pump which will relieve most pressure. The filter is the canister. In the frame rail right in front of the left rear tire.

 

[jdanna]

OK i put in a new fuel filter today.
Fuel pressure is still about the same - 37/38ish PSI.

The car definitely feels like it has more power, and the knock is less often and less severe.
I could go WOT up to 15/16ish PSI with no knock if i rolled on throttle gradually.

If i hit it hard from a stop or low speed, or let it hard downshift, knock would go up to around the first 2ish green lights on the gauge - so not so bad, but still happening.

Ignition coils are on the way, and im still waiting to hear back from turbotweak about getting a chip.

 

[jdanna]

Also i tried adjusting the fuel pressure up to 40psi and to 42 psi (at idle with the vacuum disconnected to the regulator) - and it made the problem worse. now its going into the first 3 knock LEDS at around 5 psi , and i didnt push it harder then that.

So im thinking either A. its a spark problem, or B. its a fuel volume, not pressure problem. this would make sense because there was definitly some gunk in the fuel filter. god knows whats in the tank or clogging up the screens in the tank. I think the pumps are fine since adjusting the regulator got me more pressure no problem.

Im gonna wait for my new coils to show up, try that, and if that dosnt work - im dropping the tank.
Does this line of thinking make sense or am i totally off base?

 

[mearly65]

If you saw crud in the filter then its definitely in the tank too. New coils aren't going to clean that crap out of the tank. My next step would be to drop the tank and clean everything up nicely. It's not that difficult of a job.

 

[EYE-OPENER]

If you saw crud in the filter then its definitely in the tank too. New coils aren't going to clean that crap out of the tank. My next step would be to drop the tank and clean everything up nicely. It's not that difficult of a job.

+1....you can have good pressure but volume is obviously restricted. I would drop the tank and see what she looks like. I just bought a new tank online for $135 shipped! It is well worth it to know it is perfect. I bet the strainer is not so pretty and it might be a great time to upgrade the pump. I know nobody wants to spend money.....but a few hundred bucks and a few hours worth of work is a ton better than blowing a head gasket. That option is a crapload worse and not so cheap either. You can have the tank dropped on the ground in less than an hour and will surprised at what you see...just try to make sure the tanks empty as possible

 

[eric_1984ttype]

Put a scan tool on it and get rid of the light show. The scan tool will tell you how much timing is being taken out (how bad the knock is). And let you know what your sensors and computer are seeing. Without that your just shooting in the dark. Pull the plugs and look at them. I doubt the coil is the problem. They usually start to break up when they get hot or miss like he!! when they die. Clean the tank out and put a pump and hotwire kit on it. Get a manual for the maf translator and make sure it's set properly for your maf. Make sure there is nothing loose or rattling on the car. Could he false knock.

 

[jdanna]

+1....you can have good pressure but volume is obviously restricted. I would drop the tank and see what she looks like. I just bought a new tank online for $135 shipped! It is well worth it to know it is perfect. I bet the strainer is not so pretty and it might be a great time to upgrade the pump. I know nobody wants to spend money.....but a few hundred bucks and a few hours worth of work is a ton better than blowing a head gasket. That option is a crapload worse and not so cheap either. You can have the tank dropped on the ground in less than an hour and will surprised at what you see...just try to make sure the tanks empty as possible

yup - gonna drop the tank this week hopefully.
what is a good fuel pressure to run? i cant really find a good answer to that

 

[achalmersman]

+1....you can have good pressure but volume is obviously restricted. I would drop the tank and see what she looks like. I just bought a new tank online for $135 shipped! It is well worth it to know it is perfect. I bet the strainer is not so pretty and it might be a great time to upgrade the pump. I know nobody wants to spend money.....but a few hundred bucks and a few hours worth of work is a ton better than blowing a head gasket. That option is a crapload worse and not so cheap either. You can have the tank dropped on the ground in less than an hour and will surprised at what you see...just try to make sure the tanks empty as possible

I don't understand this. Pressure is relative to volume. If you have consistent pressure (does not drop under WOT) you have adequate volume......

 

[EYE-OPENER]

I don't understand this. Pressure is relative to volume. If you have consistent pressure (does not drop under WOT) you have adequate volume......

If the strainers are jacked up and restricted he could have good pressure at idle but as the need for more fuel is there the restriction won't allow it. Just like having a jacked up filter. He saw a big difference when changing the filter and I bet he will be seeing the same junk in the tank. I have stock coils on my gn as many do and have been mid 10's with more left in it....it's not his coils. I would have found a cheapo fuel pressure gauge that can be temporarily routed where he can see it and when all the issues are there he will see fuel pressure dropping a lot. Wish you were near me cause this would be fixed in a quickness.