LEAN! Fuel Pulsation Dampner - Could It Be Causing My Problems?
 

Last season I couldnt tune or run my car worth a ----. Brand new motor at the end of the season and I never got a run out of it. No matter how much fuel I added in turboedit it would keep going lean in the upper rpms, like way lean.

The car is a 90 Crx Si, d16a6 forged internal motor, obd0, turboedit, gm 3 bar, dsm 450's, wideband 02 with digital readout.

I could add fuel and fuel and fuel while deep into boost (usually anything above 8psi I believe) and then it would start going lean, I maxed out the fuel maps, checked fuel pressure. Everything was fine.

I did a few nights of reading trying to find the problem, and came across a guy or two that apparently had the same prblem with never being able to get enough fuel. And 2 of them said that the removal of the fuel dampner on the end of the fuel rail could be the cause.

Im looking for a good answer or a good place to start so I can have a good solid season.

Thanks guys

Re: LEAN! Fuel Pulsation Dampner - Could It Be Causing My Problems?
 

fuel dampner does nothing. Sounds like you are maxing your fuel pump. Could be caused by a plugged fuel filter, line, pickup sock, or just not a big enough fuel pump.

Re: LEAN! Fuel Pulsation Dampner - Could It Be Causing My Problems?
 

I think your problem could be two fold you may be maxing out those 450's , and also if your running the stock fuel pump then you'll need a walbro 255.

Re: LEAN! Fuel Pulsation Dampner - Could It Be Causing My Problems?
 

If you use the wrong type of washer that goes on the fuel damper/banjo bolt, yes you will see the symptoms that you describe.
Ive personally worked on a car that had the wrong one installed. It behaved exactly as you describe.
It wasnt until we duct taped a FP gauge to the windshield, and ripped on it, that we figured it out.

Depending on the rail/damper/banjo you are using, some will use a washer that is serrareted on the inside diameter.

If you have access to a FP guage, and assuming this is your problem, your prerail pressure will be abnormally high, and will not decrease appropriately as manifold vacuum increases.

Re: LEAN! Fuel Pulsation Dampner - Could It Be Causing My Problems?
 

Was this on 8psi steady?

Re: LEAN! Fuel Pulsation Dampner - Could It Be Causing My Problems?
 

No this wasnt on 8 psi steady, this was on a built motor and it was still on it s way up to 18 or so psi

A few times I got there in 2nd gear pulls but the air fuels still got really lean and I would shift early, then in third they were just ridiculous.

The car has a walbro 255 pump, loud as hell, its new, its working.

I dont think Ive ever had the dampner off of this fuel rail so Im assuming its a stock washer

The onyl thing I really have changed in the fuel system is my fuel pump, new fuel filtere and a fuel pressure gauge mounted on the fuel return nut of the fuel filter

I have a liquid filled gauge I was planning on installing this year (was going to tap the rail) but I wouldnt be able to see it while driving

Re: LEAN! Fuel Pulsation Dampner - Could It Be Causing My Problems?
 

Figure it out?

Re: LEAN! Fuel Pulsation Dampner - Could It Be Causing My Problems?
 

no i need help bump

Re: LEAN! Fuel Pulsation Dampner - Could It Be Causing My Problems?
 

What is your wastegate set at? If you bosting to around 18 psi it's probably maxing out the DSM 450's.

Re: LEAN! Fuel Pulsation Dampner - Could It Be Causing My Problems?
 

I recently worked on a D16z6 that required exactly 19psi to max the ---- out of his 450's (Walbro pump on a stock FPR).
Id say your getting close to the end of the 450's, maybe.