Do i have an injector bleed down problem???
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,514
Likes: 30
From: Friendswood TX
Do i have an injector bleed down problem???
Hey guys,
Just trying to make sense of my cars issue. It has SVO 30# injectors along with some other good mods (bolt ons other than the hotcam and rockers). When the car is cold, it fires up just fine. When its warm and been sitting for a few mins... when i try to restart it, it turns over multiple times before it fires up and when it does fire, it idles up for a short while before returning to normal idle as if the engine is burning off fuel sitting in the cylinder (my guess).
When i checked the fuel pressure, it is around 50 PSI on the main rail from the pump as soon as the ignition is turned on but it bleeds down almost immediately not holding any pressure unless the car is running.
Is that normal?
Now when im driving the car, it runs great! Its just this starting issue. And if it is an injector/s leaking down, can it cause any other problems or damage to the car or am i just having to deal with the frustrating restarts?
What is a good way to check the injectors to figure out which ones are giving me the problem or should i just replace the whole set? Could anything else cause this?
Thanks in advance!
Just trying to make sense of my cars issue. It has SVO 30# injectors along with some other good mods (bolt ons other than the hotcam and rockers). When the car is cold, it fires up just fine. When its warm and been sitting for a few mins... when i try to restart it, it turns over multiple times before it fires up and when it does fire, it idles up for a short while before returning to normal idle as if the engine is burning off fuel sitting in the cylinder (my guess).
When i checked the fuel pressure, it is around 50 PSI on the main rail from the pump as soon as the ignition is turned on but it bleeds down almost immediately not holding any pressure unless the car is running.
Is that normal?
Now when im driving the car, it runs great! Its just this starting issue. And if it is an injector/s leaking down, can it cause any other problems or damage to the car or am i just having to deal with the frustrating restarts?
What is a good way to check the injectors to figure out which ones are giving me the problem or should i just replace the whole set? Could anything else cause this?
Thanks in advance!
Supporting Vendor
Joined: Mar 2008
Posts: 1,762
Likes: 14
From: Cumming Ga
hey guys,
just trying to make sense of my cars issue. It has svo 30# injectors along with some other good mods (bolt ons other than the hotcam and rockers). When the car is cold, it fires up just fine. When its warm and been sitting for a few mins... When i try to restart it, it turns over multiple times before it fires up and when it does fire, it idles up for a short while before returning to normal idle as if the engine is burning off fuel sitting in the cylinder (my guess).
When i checked the fuel pressure, it is around 50 psi on the main rail from the pump as soon as the ignition is turned on but it bleeds down almost immediately not holding any pressure unless the car is running.
Is that normal?
Now when im driving the car, it runs great! Its just this starting issue. And if it is an injector/s leaking down, can it cause any other problems or damage to the car or am i just having to deal with the frustrating restarts?
What is a good way to check the injectors to figure out which ones are giving me the problem or should i just replace the whole set? Could anything else cause this?
Thanks in advance!
just trying to make sense of my cars issue. It has svo 30# injectors along with some other good mods (bolt ons other than the hotcam and rockers). When the car is cold, it fires up just fine. When its warm and been sitting for a few mins... When i try to restart it, it turns over multiple times before it fires up and when it does fire, it idles up for a short while before returning to normal idle as if the engine is burning off fuel sitting in the cylinder (my guess).
When i checked the fuel pressure, it is around 50 psi on the main rail from the pump as soon as the ignition is turned on but it bleeds down almost immediately not holding any pressure unless the car is running.
Is that normal?
Now when im driving the car, it runs great! Its just this starting issue. And if it is an injector/s leaking down, can it cause any other problems or damage to the car or am i just having to deal with the frustrating restarts?
What is a good way to check the injectors to figure out which ones are giving me the problem or should i just replace the whole set? Could anything else cause this?
Thanks in advance!
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,514
Likes: 30
From: Friendswood TX
The car has a Holley AFPR but the adjustment screw is broken off. Doesnt necessarily mean its bad... its just stuck at that setting. When i pull the vacuum line in the FPR, should the car be running?
Ill probably replace it with a TPIS FPR just to eliminate that as a possibility and so I can adjust it when it needs to be adjusted...
Ill probably replace it with a TPIS FPR just to eliminate that as a possibility and so I can adjust it when it needs to be adjusted...
Le Mans Master
Joined: Dec 2004
Posts: 5,789
Likes: 8
From: Myrtle Beach SC
St. Jude Donor '05-'06
The car has a Holley AFPR but the adjustment screw is broken off. Doesnt necessarily mean its bad... its just stuck at that setting. When i pull the vacuum line in the FPR, should the car be running?
Ill probably replace it with a TPIS FPR just to eliminate that as a possibility and so I can adjust it when it needs to be adjusted...
Ill probably replace it with a TPIS FPR just to eliminate that as a possibility and so I can adjust it when it needs to be adjusted...
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,514
Likes: 30
From: Friendswood TX
No not while running. Just pull it off and smell for gas that may be leaking by the FPR via the vacuum hose. If gas is sucked into the intake as you shut it down it will cause a hard start when warm condition. Cold it will have had enough time to evaporate.You can also check the FP with a gauge after shutdown to see if the pressure drops.
I checked the fuel pressure. On the main rail before the FPR where the check valve is, the pump was pushing about 50 PSI as soon as the ignition was turned on and the the pressure would immediately leak down to 0 again....
Thanks for your help on this guys!
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Supporting Vendor
Joined: Mar 2008
Posts: 1,762
Likes: 14
From: Cumming Ga
Ok. I pulled the vacuum line off the bottom of the regulator and didnt see any fuel in there and it didnt drip anything. The car has been sitting over night though. Should i drive it and then check it again?
I checked the fuel pressure. On the main rail before the FPR where the check valve is, the pump was pushing about 50 PSI as soon as the ignition was turned on and the the pressure would immediately leak down to 0 again....
Thanks for your help on this guys!
I checked the fuel pressure. On the main rail before the FPR where the check valve is, the pump was pushing about 50 PSI as soon as the ignition was turned on and the the pressure would immediately leak down to 0 again....
Thanks for your help on this guys!
Le Mans Master
Joined: Dec 2004
Posts: 5,789
Likes: 8
From: Myrtle Beach SC
St. Jude Donor '05-'06
BY pulling the vac hose all this tells you if the diaphram is ruptured. the valve can also be bad . you have to pinch the return hose closed and see if it holds pressure then. If it does it is the check valve in the pump or the injectors. This is the only way you can check the regulator on the car.
Thread Starter
Melting Slicks
Joined: Jan 2008
Posts: 2,514
Likes: 30
From: Friendswood TX
Ok, i have a couple errands to run but ill try to check that tonight when i get home so i can figure out what the problem is.
Am i harming the car in any way to drive it like this?
Am i harming the car in any way to drive it like this?
