FP seems a tad high....
Thread Starter
Pro
Joined: Nov 2006
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From: Plano TX
FP seems a tad high....
Question for you all. I'm researching my rich issue.
I have an 85 with the stock TPI setup still. I just recently sent my stock 24# injectors to Rich @ Cruzin. I also had to replace the diaphragm in my stock fuel pressure regulator. I did this all while I replaced my EGR and redid my intake manifold gasket. Timing is set to 6*BTDC.
Ok, with that history out of the way, I currently run rich during open loop and WOT. I suspect both conditions because at WOT, it's back in open loop anyways, right?
Ok, so I checked my FP by bumping the key over. It's sitting at 46. That seems a bit high considering it's stock. After starting the car it'll sit around 46 (vacuum connected).
I took it for a spin with the pressure gauge attached and noticed when I would kick it to WOT, the pressure would jump to 50 to 52 then come back down.
I'm thinking the regulator is crapped out on this. I'm interested in hearing other's opinions.
The FSM calls for no greater that 39 PSI, but I see other discussing running at higher PSI.
I have an 85 with the stock TPI setup still. I just recently sent my stock 24# injectors to Rich @ Cruzin. I also had to replace the diaphragm in my stock fuel pressure regulator. I did this all while I replaced my EGR and redid my intake manifold gasket. Timing is set to 6*BTDC.
Ok, with that history out of the way, I currently run rich during open loop and WOT. I suspect both conditions because at WOT, it's back in open loop anyways, right?
Ok, so I checked my FP by bumping the key over. It's sitting at 46. That seems a bit high considering it's stock. After starting the car it'll sit around 46 (vacuum connected).
I took it for a spin with the pressure gauge attached and noticed when I would kick it to WOT, the pressure would jump to 50 to 52 then come back down.
I'm thinking the regulator is crapped out on this. I'm interested in hearing other's opinions.
The FSM calls for no greater that 39 PSI, but I see other discussing running at higher PSI.
Last edited by evmlarry; May 27, 2007 at 12:51 AM.
Thread Starter
Pro
Joined: Nov 2006
Posts: 638
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From: Plano TX
Ok, I've finally found the location to troubleshoot my rich issues, FP being the 1st item on the list, in my FSM.
Think I'll probably have to pitch that regulator and get a new one. Might as well go for an AFPR.
Think I'll probably have to pitch that regulator and get a new one. Might as well go for an AFPR.
Le Mans Master
Joined: Feb 2006
Posts: 8,753
Likes: 9
From: Louisiana
The 85 uses a lower pressure than the later years due to the 24 lb/hr injectors. It sounds like your pressure is too high. Should be in the mid 30's. I would try and lower the fuel pressure. Does the FPR diaphram leak? The spring might be bad.
You can either replace the diaphram and spring or install a AFPR so you can adjust the fuel pressure. I have a Holley AFPR on my 86 and like being able to adjust the pressure. I paid ~$90 for it.
You can either replace the diaphram and spring or install a AFPR so you can adjust the fuel pressure. I have a Holley AFPR on my 86 and like being able to adjust the pressure. I paid ~$90 for it.
Thread Starter
Pro
Joined: Nov 2006
Posts: 638
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From: Plano TX
This is actually the brand new diaphragm... that's what makes it strange. I think I'll probably look into replacing that regulator for the same reason you posted... it'll make things easier for me to tune later on.
