Another Bogging down issue

[completelyrevlimited]

Hi there, im a bit new to this forum, or any forum in general, so excuse me if im posting in the wrong section,

but I have a 1991 325I convertible that has been giving me issues recently and I cannot pin point where or what it is or coming from.

Symptoms: Can't rev past 3000-4000 RPMs while at idle, especially under load. The Rev Limiter Issue
Strange Happenings:
1. I've noticed that there seems to be a small hissing sound under the passenger side of the exhaust, either after the header, or right before the cat. (Will smoke test when I get the chance.)
2. There seems to be an odd grinding sound when actually trying to go past 4k RPMs. I would try to describe it as maybe a Aluminum can rolling on a hard surface? Hard to say.
3. Took out spark plugs after test driving, completely dry with signs of running lean, white powdery like a donut.
4. Smells kind of lean, almost like a firework sometimes, or like hot air?

Things I've Done:
-> I've just today replaced my Fuel Pump, and hooked up a fuel pressure gauge to the fuel rail, get about a steady ~39.5 PSI while at idle, ~43+ at load.
-> Eliminated all seen vacuum leaks. (No more smoke visible.), Oil cap and dipstick show a significant drop in idle when removed
-> New spark plugs, double checked gap
-> Checked cap and rotor, seemed good, scraped the pins to verify decent contact.
-> Wires seem good, (Checked each cylinder, removed cables significant change to idle and noticeable miss)
-> Coolant temp sensor seems slightly out of spec (~1800Ω, reading while cold), will recheck.
-> CPS sensor seems good, replaced with old one and definitely ran slightly worse, (Didn't have the problem with old one), read ~.600 Ω's

Modifications:
-> Currently running an MAF sensor conversion from SSSQUID
-> Currently running a tune from SSSQUID, with ECU starting with 5
-> 19# Injectors, (Pink top) 0-280-155-832, (Bought from ebay, can I get any advice if these are viable, everything has been running good up until now with these installed)


I've read around a few forums, scouring to find the solution, but as someone said, they've seen people post the issue but never actually gave a solution.
Any suggestions? I daily this car and has been reliable every day for the past two years, up until now. Thanks :)

[It's Soda Not Pop]

What is the stomp test telling you?

[e30davie]

Will it free rev?

[completelyrevlimited]

Will it free rev?

No, it feels like theres a limiter on it @ 3500-4000 RPMs

What is the stomp test telling you?

Will check in the morning when I get up, if its not that, what's the next step in testing?
If its the TPS, I checked it and seemed to be giving resistance and open looping between the switches.+

[It's Soda Not Pop]

No, it feels like theres a limiter on it @ 3500-4000 RPMs



Will check in the morning when I get up, if its not that, what's the next step in testing?
If its the TPS, I checked it and seemed to be giving resistance and open looping between the switches.+

You need to see what codes are being thrown if any. Also You could try resetting the DME. Unplug the battery

[completelyrevlimited]

You need to see what codes are being thrown if any. Also You could try resetting the DME. Unplug the battery

In that case, I currently have it unplugged for overnight, to see if its possible that somehow the previous vacuum leaks are storing old fuel trim data? I'll have to test drive it for a bit and then check codes. So.. Will do!

[It's Soda Not Pop]

I also see that you are using SSSquid tune. You can give them a call and/or email. I use them as well.

[completelyrevlimited]

I also see that you are using SSSquid tune. You can give them a call and/or email. I use them as well.

Yes, it works great.
Which makes me think this isn't a ECU / Tune issue. The problem also persists with their MAF conversion and stock VAM

[It's Soda Not Pop]

Here is a list of the codes

[82eye]

have you done any engine mods or is it just the chip, maf, and injectors ? definitely sounds like the ecu is pulling the map at higher rpm. 19# injectors are a bit much on a stock engine, i don't think it's at the root of the issue though. sssquid usually recommends an injector with their tune, or runs stock, i'd go with their suggestion.

i noticed jay has dropped the maf conversion kit which saddens me. i hope it comes back. i'm going to run their 1.5 tune on an engine with mild mods and exhaust. i went with their recommended 17/19 lb/hr 4 pintle injectors. if you upgrade anything in an injector get away from the ancient inefficient single pintle capped injectors.

disconnecting the battery and letting the ecu reset is a great idea. it's possible you solve it on that alone.

[completelyrevlimited]

[QUOTE=It's Soda Not Pop;n10071826]Here is a list of the codes

Finally got to resetting it for the night. Got code 1222 that flashed for a second then went away. Its stored.

However, new symptom / worsening : Car wont drive past 1k now, and idles at what looks like 500-600 rpms now.

have you done any engine mods or is it just the chip, maf, and injectors ? definitely sounds like the ecu is pulling the map at higher rpm. 19# injectors are a bit much on a stock engine, i don't think it's at the root of the issue though. sssquid usually recommends an injector with their tune, or runs stock, i'd go with their suggestion.

i noticed jay has dropped the maf conversion kit which saddens me. i hope it comes back. i'm going to run their 1.5 tune on an engine with mild mods and exhaust. i went with their recommended 17/19 lb/hr 4 pintle injectors. if you upgrade anything in an injector get away from the ancient inefficient single pintle capped injectors.

disconnecting the battery and letting the ecu reset is a great idea. it's possible you solve it on that alone.

No engine mods, Im running the Pink top injectors as that was an option with their tune. I believe they also brought back the MAF conversion as a new item, completely new version of it :D

[digger]

what does the tach do when the car gets its panties in a bunch?

[completelyrevlimited]

what toes the tach do when the car gets its panties in a bunch?

Just kind of stays, no noticeable bouncing, anything really. Im stumped.

Update: Just changed out my Chip to the stock chip, now it wont start at all.

[82eye]

have you got the original afm ? you might try that.


edit : i know it's an odd one but check your blue temp sensor. it sends info to the ecu to help determine how lean or rich to run based on temp. all sorts of weird driving stuff can happen if they go bad.

[completelyrevlimited]

have you got the original afm ? you might try that.


edit : i know it's an odd one but check your blue temp sensor. it sends info to the ecu to help determine how lean or rich to run based on temp. all sorts of weird driving stuff can happen if they go bad.

Have one arriving on the 20th, Currently running the AFM to rule that as an issue already :/