bad fuel pump or pressure regulator?
#16
Re: bad fuel pump or pressure regulator?
There are many after market adjustable fuel pressure regulators out there and they mostly go for around 125 to as much as 300+. As far a stock reguator (non-adjustable) I don't know what the cost is: and you really don't need an adjustable one on a moderately modded engine. The stock regs are set for stock pressures of around 43-46 WOT and around 8 less otherwise.
So, obviously you don't need to adjust the fp. Your PCM determines the A/F ratio so changing the fp (on an OBD11) will only cause the PCM to readjust the pulse of the injectors to bring the A/F back in line with the program. On the OBD11, tuners can program the PCM for a particular A/F to maximize your power depending on your setup.
I'm not certain about the outcome of altering the fp on an OBD1 pcm regarding the response of the pcm to your adjustments vis a vis adjusting the injector pulse. But again, a tuner can program the OBD1 to maximize the A/F.
So if you use an Adjustable fp regulator to lean you A/F for increased power on a OBD1 pcm, perhaps you can affect the long term A/F and maintain the power with the leaner A/F (the tuners on the board should be able to explain this (whether or not this is the case).
Bottom line: You might just get a replacement regulator if your's is boogered and the cost may be quite reasonable.
My point is: if you are set on getting an adjustable FPR, you should make sure that if it is the kind that "modifies" your stocker that your stocker might have some parts that need to be good in order for the AFPR to work.
I say this because, I somehow doubt that you are going to find a complete (plug and play) AFPR for 35 bucks.
Also, consider that the stock regulator sits snugly against the firewall and not just any sized regulator is going to fit very well. Take it for what it's worth.
So, obviously you don't need to adjust the fp. Your PCM determines the A/F ratio so changing the fp (on an OBD11) will only cause the PCM to readjust the pulse of the injectors to bring the A/F back in line with the program. On the OBD11, tuners can program the PCM for a particular A/F to maximize your power depending on your setup.
I'm not certain about the outcome of altering the fp on an OBD1 pcm regarding the response of the pcm to your adjustments vis a vis adjusting the injector pulse. But again, a tuner can program the OBD1 to maximize the A/F.
So if you use an Adjustable fp regulator to lean you A/F for increased power on a OBD1 pcm, perhaps you can affect the long term A/F and maintain the power with the leaner A/F (the tuners on the board should be able to explain this (whether or not this is the case).
Bottom line: You might just get a replacement regulator if your's is boogered and the cost may be quite reasonable.
My point is: if you are set on getting an adjustable FPR, you should make sure that if it is the kind that "modifies" your stocker that your stocker might have some parts that need to be good in order for the AFPR to work.
I say this because, I somehow doubt that you are going to find a complete (plug and play) AFPR for 35 bucks.
Also, consider that the stock regulator sits snugly against the firewall and not just any sized regulator is going to fit very well. Take it for what it's worth.
#17
Re: bad fuel pump or pressure regulator?
Well i checked around and found some interesting results. All sites i found that were NOT GM related said the FPR was for 93-97. All sites i found that WERE GM related, had two different part numbers for 94-95 and 96-97. Then i went to three places to check prices and part numbers. here's the results
Part store 1: 93-97 FPR, $83
Part store 2: 93-97 FPR, $70
Dealer: 94-95, $140...96-97, $70
So the two parts stores said they use the same regulator from 93-97, but the dealer said they were two different parts simply because the computer he was looking at said they were under different part numbers. i thought it was interesting.
Part store 1: 93-97 FPR, $83
Part store 2: 93-97 FPR, $70
Dealer: 94-95, $140...96-97, $70
So the two parts stores said they use the same regulator from 93-97, but the dealer said they were two different parts simply because the computer he was looking at said they were under different part numbers. i thought it was interesting.
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chevroletfreak
LT1 Based Engine Tech
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07-04-2005 05:00 PM