ECM Questions 240z to 280z/zx swap??

[Zed Head]

Just an observation - the AFM pictured in UFL's Post#6 is A31 624 000. EuroDat added a picture of an A31 625 000 in Post #12.

[Unfairlady]

Yeah I was saying I don't have my pressure gauge to check. I coulda swore I had a pressure regulator with a gauge attached to it and I was just going to put it on there to check the pressure with the gauge. not to regulate the actual pressure of the fuel. And yes :stupid: I just looked through the thread and saw that again and it reminded me.

I apologize and I will PM after I finaly get a chance to check to see if my fuel pressure is good. I think it was surging last night when I started it so I think that there is something clogged up somewhere but even if thats so it may not be all of my problem.

Thanks

[EuroDat]

Also handy to buy enough hose so you can tape the gauge to the wiper arm and view it through the window while test driving. You wont need it at this stage, but later it could handy to see what it does when driving.

[Unfairlady]

Alright so I put a fuel pressure gauge in and heres what I got what the fuel pump kicks on before the car start:

And this is while its running at idle:

And it would increase with the R's up to like 45 psi. It'll still rev like i said but under torque it wont go above 2500rpm. and It starts to get worse the longer the car runs.

I really really wish I had a l24 and carbs... :disappoin

[Zed Head]

The numbers are high by about 9 psi. It's odd because your pictures show what appears to a be a stock fuel pressure regulator (FPR) with the vacuum hose attached. There's an old trick people do where they dent the top of the regulator to put preload on the internal spring to raise fuel pressure. I wonder if the PO did something like that.

This wouldn't really explain the lack of power. You would have a gassy exhaust smell and might foul plugs but it would probably still rev higher with reasonable power.

Overall, just another wrongness. I still wonder about the AFM/ECU match as a cause. These engines will actually run without an AFM, on idle fuel enrichment, indicated to the ECU by the TPS idle position. With high fuel pressure you might have just enough fuel to match the air to get you to 2500 RPM. You might not be getting any AFM enrichment fuel at all. Try disconnecting the AFM plug and see if anything is different. That would tell you something.

[EuroDat]

Looks like the FPR is building up to much pressure. Seems to be about 15psi to high, although that might be to your advantage with the NA injectors on a turbo setup. The higher pressure wil compensate for the lower cc value of the na injectors.

If I recall correctly, don't have my notes handy atm. I was getting 48psi when I clamped the return line shut, when the vacuum line is disconnected it went to 35psi and at idle with vacuum line connected it sat around 26psi.

Chas

[superlen]

I think the PO was very creative in getting the mismatched components to at least start and halfway run the car. I understand your frustration and desire for some carbs, but don't give up on the FI yet. With the correct parts, it will be far better than a pair of metered leaks hanging on the side of the intake.

BTW, I saw your PM and I'll get a NA AFM out to you to play with. I'll also check to see if I have a spare FPR. I can assure you the NA AFM isn't going to fix things until your fuel pressure is correct as well. It also will think you have 185cc NA injectors. Let's just hope those haven't been swapped as well.

Lenny

[Unfairlady]

That's you guys have been so helpful. Well I do have a regulator on it now so I can dial the fuel pressure in just right. And I believe they are all NA injectors. They are all that light green color and I thought the turbo ones were like a darker color of some sorts..

[superlen]

Those injectors sound like the right ones. You should be good to go.

Lenny

[madkaw]

Hey, saw your pics on FB. I'm right down the road from you in Btown.

Now I could help you out, but I'm damn expensive - but I'm good

Seriously , I'll just trade you my tripled L24 for your L28ET

Okay, maybe not.

You've got a lot going on there, could be partial line blockage driving up FP.

May I suggest MS

Anyways, I'm close by if I can help in anyway

[Unfairlady]

Hey, saw your pics on FB. I'm right down the road from you in Btown.

Now I could help you out, but I'm damn expensive - but I'm good

Seriously , I'll just trade you my tripled L24 for your L28ET

Okay, maybe not.

You've got a lot going on there, could be partial line blockage driving up FP.

May I suggest MS

Anyways, I'm close by if I can help in anyway

I would run a Mega Squirt but I would rather not deal with that. I had problems with my last MS.

And once I get a NA AFM and go threw it alittle more I may take you up on that offer. Are you apart of "IMIN"?

[superlen]

If you want an aftermarket controller & don't mind waiting a few months, just get a HellFire Classic. It just replaces the stock ECU and 5 mins later... "poof" you can read all your sensors & have complete tuneability. No wiring, no chasing down parts...(unless you just want to change). It can also run with any combination of AFM (or none at all), injectors, Fuel pressure, cam, ect. Even if your AFM has been adjusted out from factory specs, you can adjust for that in software.

I think the problem may be moot though. I really think the NA AFM I sent you from my running car will make a big difference and get you at least close to the ballpark. Hopefully it showed up yesterday or will today.

Len