MyE28.com

My 535i turbo has run like poop since replacing my injectors with 42#'s (0280150558). I made the changes in megasquirt but the car is running much much richer than before. I thought maybe I got scammed and received some Chinese injectors, but i sent them off to a injector shop and they all flow tested very well.
Are there any other tests I could perform on the high impedance injectors? Otherwise, I was considering to buy a second set like this:
http://www.ebay.com/itm/6X-Green-Giant- ... cb&vxp=mtr

What were in it before? And define "made the changes"

30#'s hi imp were there before. Now, 42 hi imp. I was running too close to 100% duty cycle under boost. Under the "Engine Constants" I selected the "Required Fuel" tab and I changed to 42's. Car ran pretty well before the injector change. Barely idles now.

Injectors can vary considerably. I went from cheap 42# injectors to good ones of the same exact specifications and still had to alter my VE table quite a lot to get it running right. If all your settings are correct, then you are just going to have to do some tuning. I would expect slight changes needed even swapping matching injectors in. At least my experience has shown this.

The issue is trying to decide where to invest in next to fix the issue. I did try tuning - and sent my msq file to Matt at DIYautotune, and he said everything looked fine. I was beginning to wonder if my wideband (AEM) o2 sensor needs to be replaced, although it has about 10,000 miles on it since I put it in. The fuel injector place thought I had quality injectors, so that is why I wanted to see if there were any further tests I could do myself since the car ran pretty well with the old 30lbs.

Is your trouble limited to idle or everywhere? Small injectors are typically great for idle tuning. I hate tuning idle, never could get my m30 to run smooth at anywhere near stoich, also running 42#ers. What is the AFR in question? Hows it run under driving conditions? If idle is the only area with issue then tuning is going to be the answer.

I can not get it to the point where I can drive on the street. It runs so poorly at idle that I am limited to seeing how it runs elsewhere. My friend's e28 turbo has 60's and his car runs damn smooth at idle.

Have you tried shifting the req. fuel #?
If you are too rich, shift the req fuel # lower, vice versa if lean.
I would expect to retune the ve, playing with req fuel should shift the ve map to something that will kinda work. Then you can autotune ve , or datalog and analyze with megalog viewer.
marc

Kelvin sent me his msq since he also uses 42's. He said his tune idles really well. I loaded it on mine, and my car still ran terribly. I played with the VE map before getting Kelvin's tune. Still no luck. That's why it made me wonder if these injectors are crap.

charofire wrote:Kelvin sent me his msq since he also uses 42's. He said his tune idles really well. I loaded it on mine, and my car still ran terribly. I played with the VE map before getting Kelvin's tune. Still no luck. That's why it made me wonder if these injectors are crap.

Have you double checked to make sure the injectors are still batched/wired correctly?