I’m having the same issue with low fp (34psi then slowly drops) on my 86 n/a. Replaced everything in fuel system from pump forward including hoses, filter, fpr, injectors etc. There are no leaks that I can find so am thinking pump is faulty. Without modifying system, can you recommend fuel pump?
Okay, now I know I can get a fuel pressure testing kit from an Auto parts store to test the fuel pressure. I also believe the correct fuel pressure is 37 psi like you said in the video. What's the best way to remove the stubborn fuel hose from the filter or injector side? I've tried to do this before on another Z and it just wouldn't come off after being on there for over 30 years.
The best way to get the hose off it to just cut it off and replace it with a new hose. A few dollars at the auto parts store and a blade makes it so much easier. But I do agree that it sounds like the idle valve is the issue. Have you tried adjusting it per the fsm?
@@TheZGarage I see how that might be a good approach as a last resort, but I don't really want to cut the hose if it's good. I always felt like the hoses at autozone weren't of the same quality and often aren't the exact size. They'll work as a temporary fix. I haven't tried to adjust the idle screw at the back of the IACV yet because it's so difficult to get to and I haven't had time. I may try that later this week when I have more time. However, I can tell you that the cylinder on the IACV makes a clicking sound and if you place your hand over you'll feel a thump when the battery is connected but the car is not turned on. I think the cylinder activates the solenoid which controls the valve in order to open and close.
I have the same tank that came in my car. I dropped it and cleaned it out when I first got the car. I have a video on it, just look at the top videos on my channel
Honestly if you have a stock fuel setup, a stock fpr is what I would recommend. Anything aftermarket isn't going to fit well and you'll have to add a bunch of fuel line to put it somewhere else. It can be done though and well known brands like aeromotive are what I would recommend if that the way you're going to go.
@@TheZGarage yup I’m already in contact with a local shop trying to get my hands on one of the aeromotives. I have a AEM 340 lph fuel pump that I installed. I don’t think my stock fpr can handle that much pressure. I think it might be what’s causing my car to not wanna start right up in cold start. I’ve changed the chts sensor and bunch of other things. I’m hoping this is the last thing for now I need to change in the engine for awhile.
That's probably a good guess. Have you checked the ecu for any codes? Have you inspected your CAS at all? That can also cause start up issues. I have heard that too much fuel flow can be bad for small injectors so if those don't change anything, I would also try downsizing the pump. You can get cheap walbro pumps around 100 lph for super cheap online. If I remember correctly, the stock pump is 70 lph
@@TheZGarage I’m trying to gain power so if necessary I’ll just upgrade the injectors and get nistune. I have not checked the CAS. no one has suggested it but I’ll do that right now.
Ah I gotcha. You're probably turbo then? If so injectors shouldn't be the thing holding you back from starting. CHTS and CAS are usually the two that affect starting the most so CAS would be my next bet
I’m having the same issue with low fp (34psi then slowly drops) on my 86 n/a. Replaced everything in fuel system from pump forward including hoses, filter, fpr, injectors etc. There are no leaks that I can find so am thinking pump is faulty. Without modifying system, can you recommend fuel pump?
There is also a strong gas smell after running for a minute or two…
Okay, now I know I can get a fuel pressure testing kit from an Auto parts store to test the fuel pressure. I also believe the correct fuel pressure is 37 psi like you said in the video. What's the best way to remove the stubborn fuel hose from the filter or injector side? I've tried to do this before on another Z and it just wouldn't come off after being on there for over 30 years.
The best way to get the hose off it to just cut it off and replace it with a new hose. A few dollars at the auto parts store and a blade makes it so much easier. But I do agree that it sounds like the idle valve is the issue. Have you tried adjusting it per the fsm?
@@TheZGarage I see how that might be a good approach as a last resort, but I don't really want to cut the hose if it's good. I always felt like the hoses at autozone weren't of the same quality and often aren't the exact size. They'll work as a temporary fix. I haven't tried to adjust the idle screw at the back of the IACV yet because it's so difficult to get to and I haven't had time. I may try that later this week when I have more time. However, I can tell you that the cylinder on the IACV makes a clicking sound and if you place your hand over you'll feel a thump when the battery is connected but the car is not turned on. I think the cylinder activates the solenoid which controls the valve in order to open and close.
Where did you find a gas tank? I’ve been looking for one everywhere
I have the same tank that came in my car. I dropped it and cleaned it out when I first got the car. I have a video on it, just look at the top videos on my channel
Any recommendations on a upgraded FPR for the z31?
Honestly if you have a stock fuel setup, a stock fpr is what I would recommend. Anything aftermarket isn't going to fit well and you'll have to add a bunch of fuel line to put it somewhere else. It can be done though and well known brands like aeromotive are what I would recommend if that the way you're going to go.
@@TheZGarage yup I’m already in contact with a local shop trying to get my hands on one of the aeromotives. I have a AEM 340 lph fuel pump that I installed. I don’t think my stock fpr can handle that much pressure. I think it might be what’s causing my car to not wanna start right up in cold start. I’ve changed the chts sensor and bunch of other things. I’m hoping this is the last thing for now I need to change in the engine for awhile.
That's probably a good guess. Have you checked the ecu for any codes? Have you inspected your CAS at all? That can also cause start up issues. I have heard that too much fuel flow can be bad for small injectors so if those don't change anything, I would also try downsizing the pump. You can get cheap walbro pumps around 100 lph for super cheap online. If I remember correctly, the stock pump is 70 lph
@@TheZGarage I’m trying to gain power so if necessary I’ll just upgrade the injectors and get nistune. I have not checked the CAS. no one has suggested it but I’ll do that right now.
Ah I gotcha. You're probably turbo then? If so injectors shouldn't be the thing holding you back from starting. CHTS and CAS are usually the two that affect starting the most so CAS would be my next bet