Running Rich... spark plugs anyone?
12-26-2002, 12:38 PM
#1
Safety Car
Thread Starter
Running Rich... spark plugs anyone?
My last DTC code is a P0172. System running Rich. Supposedly...
the Vortech FMU doesn't start supplying more fuel until it sees boost, but I suppose the fuel pump has increased fuel-pressure such that the car keeps tripping the DTC.
Solution (1): Get an adjustable FMU which can work with boost, yet gives adjustability to the base-line fuel-pressure... any recommendations?
Solution (2): Get some other spark plugs that might burn up the gas a little better? I really think my plugs are fouled as well. This is a cheaper first step than Solution (1). I need recommendations on plugs for this please.
Thanks!
the Vortech FMU doesn't start supplying more fuel until it sees boost, but I suppose the fuel pump has increased fuel-pressure such that the car keeps tripping the DTC.
Solution (1): Get an adjustable FMU which can work with boost, yet gives adjustability to the base-line fuel-pressure... any recommendations?
Solution (2): Get some other spark plugs that might burn up the gas a little better? I really think my plugs are fouled as well. This is a cheaper first step than Solution (1). I need recommendations on plugs for this please.
Thanks!
12-26-2002, 02:29 PM
#4
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Most likely the fuel pump pushing too much for the stock FPR to release back to the tank. What is you fuel pressure at idle without vacuum hooked up to the regulators??
So your FT value must be hitting -21.5% to trip that code.
Fun stuff, I had the opposite happen when I swapped the blower on my old GTP. It didn't seal correctly and caused a small vacuum leak. But since it was a MAF system that un-metered air caused it to go lean at high vacuum levels setting the code quickly.
I would try to address the rich condition and not try to burn the extra fuel. It will hurt fuel economy and emission and slowly get to the catalyst. There are a couple of routes to fix this and you mentioned one.
Aren't there any adjustments on your regulator?? You could modify or change the disks in your unit. But what would be better is move to an adjustable FMU Like the SFMU from Vortech . This provides several adjustments which would cure your problems.
One other, albeit very crude, method would be to lower the MAP output by using resistors or a potentiometer as a voltage divider. Or you could use a VAFC which would accomplish the same thing and allow for better tuning at varying RPMs.
But IMO, the SMFU would be the best bet.
So your FT value must be hitting -21.5% to trip that code.
Fun stuff, I had the opposite happen when I swapped the blower on my old GTP. It didn't seal correctly and caused a small vacuum leak. But since it was a MAF system that un-metered air caused it to go lean at high vacuum levels setting the code quickly.
I would try to address the rich condition and not try to burn the extra fuel. It will hurt fuel economy and emission and slowly get to the catalyst. There are a couple of routes to fix this and you mentioned one.
Aren't there any adjustments on your regulator?? You could modify or change the disks in your unit. But what would be better is move to an adjustable FMU Like the SFMU from Vortech . This provides several adjustments which would cure your problems.
One other, albeit very crude, method would be to lower the MAP output by using resistors or a potentiometer as a voltage divider. Or you could use a VAFC which would accomplish the same thing and allow for better tuning at varying RPMs.
But IMO, the SMFU would be the best bet.
12-26-2002, 02:44 PM
#5
Safety Car
Thread Starter
SFMU
The SFMU would fix the pressue @ idle (or in the vacuum region)
and allow an adjustable boost vs. psi curve. I got to ask these guys if they will exchange the darn thing... don't want to buy two!
The Comptech FPR must be doing the same thing.
I won't try toying with the MAP sensor as I wouldn't want issues when there actually is boost... especially timing issues.
I need to get a fuel pressure guage. I need something without
cutting that hose... and that screws into either the FPR or the connection between the hard-line from the fuel-tank to the host.
There are no adjustments to my regulator. It's the 12:1 Vortech FMU. It's really not supposed to do anything until it encounters boost... so the problem here is that the stock regulator can't send all the fuel through the return line. I've had inline pumps before with this setup and this is a first!
A question on the code. I initially got a P0170 as well. Fuel Trim malfunction (bank 1). This was a 'pending' code. The P0172 set off the MIL. Is the 'bank 1' vs 'bank 2' refer to cylinder banks? If so... on the CL-S, which is bank 1?
Re TypeR's question: The stat + fan switch doesn't contribute to this problem at all
and allow an adjustable boost vs. psi curve. I got to ask these guys if they will exchange the darn thing... don't want to buy two!
The Comptech FPR must be doing the same thing.
I won't try toying with the MAP sensor as I wouldn't want issues when there actually is boost... especially timing issues.
I need to get a fuel pressure guage. I need something without
cutting that hose... and that screws into either the FPR or the connection between the hard-line from the fuel-tank to the host.
There are no adjustments to my regulator. It's the 12:1 Vortech FMU. It's really not supposed to do anything until it encounters boost... so the problem here is that the stock regulator can't send all the fuel through the return line. I've had inline pumps before with this setup and this is a first!
A question on the code. I initially got a P0170 as well. Fuel Trim malfunction (bank 1). This was a 'pending' code. The P0172 set off the MIL. Is the 'bank 1' vs 'bank 2' refer to cylinder banks? If so... on the CL-S, which is bank 1?
Re TypeR's question: The stat + fan switch doesn't contribute to this problem at all
12-26-2002, 02:51 PM
#6
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Re: SFMU
Originally posted by allmotor_2000
There are no adjustments to my regulator. It's the 12:1 Vortech FMU. It's really not supposed to do anything until it encounters boost... so the problem here is that the stock regulator can't send all the fuel through the return line. I've had inline pumps before with this setup and this is a first!
A question on the code. I initially got a P0170 as well. Fuel Trim malfunction (bank 1). This was a 'pending' code. The P0172 set off the MIL. Is the 'bank 1' vs 'bank 2' refer to cylinder banks? If so... on the CL-S, which is bank 1?
There are no adjustments to my regulator. It's the 12:1 Vortech FMU. It's really not supposed to do anything until it encounters boost... so the problem here is that the stock regulator can't send all the fuel through the return line. I've had inline pumps before with this setup and this is a first!
A question on the code. I initially got a P0170 as well. Fuel Trim malfunction (bank 1). This was a 'pending' code. The P0172 set off the MIL. Is the 'bank 1' vs 'bank 2' refer to cylinder banks? If so... on the CL-S, which is bank 1?
Don't worry about the bank reference, we will only ever see Bank 1. There are OBDII specifications that are in place but not used except in some rare cases. It was more for planning for the future when each cylinder might get monitored. Right now on our car it has no bearing and all fuel aspects will be related to Bank 1.
12-26-2002, 03:05 PM
#7
Safety Car
Thread Starter
Stock FPR
Do you know if this is the 'standard' stock FPR used in most Honda/Acura motors? I might try something like swapping my stock FPR with something from a 98 prelude... because I had a '98 prelude with the same FMU and an inline MSD pump. Line pressure was definately very high.... but no DTC - might be worth
a try IF they are different!
a try IF they are different!
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12-26-2002, 06:02 PM
#9
Senior Moderator
Re: SFMU
Originally posted by allmotor_2000
Re TypeR's question: The stat + fan switch doesn't contribute to this problem at all
Re TypeR's question: The stat + fan switch doesn't contribute to this problem at all
12-26-2002, 06:43 PM
#10
Safety Car
Thread Starter
Scalbert did all the pioneering with the Mugen stuff... so I was very confident there would be no problems with those mods. It's a bit of a pain to R&D all this stuff yourself... no wonder Comptech charges much moola (that's $$) for their stuff! I'll fix this fuel-thing... probably from our discussion the SFMU might be the way to go!
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