Dinan chipped M50NV weird problem

[SamE30e]

Hey,

I recently put a Dinan chip in my M50 non vanos swap, it makes a good amount more power, but it's weird. In 2nd gear if I go from like 2500 to 6500 it feels like it's coming on in steps, like it's got little torque from 2500 to 3500, then it pulls hard, then slowly drops off after 5000. And it's not consistant either. Sometimes the car won't have that pull, like it's down on power.

I think it might be a fueling issue, I have a narrowband o2 gauge I want to hook up to give me an idea of whats happening (I know narrow bands aren't accurate at all but it will give me a general idea if it's lean, rich or normal). I need to know what the o2 signal wire is, what colour and where I can tap into it.

Thanks

Sam

[Danny]

Afrs are off

[SamE30e]

What would cause it. I'm thinking fuel filter maybe, fuel starvation?

[Danny]

Do you need bigger injectors with that chip?

[zav3n]

look into fuel pumps the 1991 318is chassis have only 1 in-tank fuel pump... if u have the money go walbro... and some pink-tops or at least 19lbs injectors should do the trick..

[nando]

look into fuel pumps the 1991 318is chassis have only 1 in-tank fuel pump... if u have the money go bosch 040/044 and some pink-tops or at least 19lbs injectors should do the trick..

fixed.. walbro is for people without money. :p

[mentaleeill]

i highly doubt you will need a upgraded fuel pump for a dinan chipped nv m50. ive seen guys run 350 rwhp on fi setups retaining the stock pump, if you suspect yours is bad just get a stock replacement, why deal with the noise if you dont need to. change your filter first. suprised that you worried about a chip before the basic maintenance shit anyway. hows your plugs and air filter?

[SamE30e]

I don't suspect the pump is bad. Maybe the sock is covered in shit. I'll check that tomorrow and spray the coils down to see if any are cracked.

Wouldn't changing the injectors be a bad idea without a chip for it?

[PiercedE30]

Not if it's a big change. If you go to 19's, the computer will adapt to the larger injectors. Not ideal, but it works.

[SamE30e]

What do the pinks come out of? M52?

I'm going to check the sock tomorrow.

[zav3n]

i never said ur pump was bad. u might need another pump to help supply the fuel in the high rpms. i have a 91' 318is m50tu that was hesitating, added junkyard jag xj6 pump + ford 19lbrs runs nice now.

[SamE30e]

New discovery, at less then 90% throttle it runs fine between 3000 and 5000, but if I go WOT when the ecu switches to a map, it goes lean.

[SamE30e]

Changed the fuel filter. Still does it.

It seems to do it when it's warmer out.

I also switched from a 402 to a 403 ECU when I put the chip in.