Loss of power or Misfire at 4k RPM?

[Graebmw95]

I've had a small misfire intermittently for the past couple months. It happens then it goes away for a while. But today for some reason its real bad, at 4k the car feels like a total loss of power. It jolts and jerks and doesn't accelerate at all. I just recently took the injectors off to see if there were clean, they looked clean.

But when I took then off i noticed this


A quick trip to O'reilys and i was able to fix it no problem.

This fixed the problem for a couple weeks, because i was having the same issue, ( just not as bad as now)
And so i thought i fixed the issue. Well i guess not because this shits happening.

It has new oil
New cats
New filters
Im pretty sure the plugs and wires are new, but im going to check here soon to double check. Ill post pictures.

Oh! Almost forgot, I also suddenly lost a lot of fuel economy. I was at 24 mpg now my computer is reading 18. I also put gas in yesterday to half a tank, and now i have a quarter left and hasn't been 24 hrs yet sense i put gas in.

So i'm at a loss. Any one els have extreme power loss at 4k or anything? Please help i'm real discouraged and am concerned for te car. Lol

Also it's a 1984 318i just so yall know.


Sent from my iPhone using Tapatalk

[Acet]

Next time this happens, pull over and with ignition ON (the motor not running) listen to clicking coming from the black rectangular box located next to the fuel pump relay. I know quite a few members here, including myself, have had a very similar problem. Who knows, maybe it will help.

http://www.r3vlimited.com/board/showthread.php?t=317836&page=2

in post number 17, a video is available with the buzzing/clicking of the part im referring to.

[Graebmw95]

Next time this happens, pull over and with ignition ON (the motor not running) listen to clicking coming from the black rectangular box located next to the fuel pump relay. I know quite a few members here, including myself, have had a very similar problem. Who knows, maybe it will help.

http://www.r3vlimited.com/board/showthread.php?t=317836&page=2

in post number 17, a video is available with the buzzing/clicking of the part im referring to.

Should it be clicking or no?! I'm sorry this isn't really my area of expertise lol


Sent from my iPhone using Tapatalk

[Acet]

Also, seeing that you're a new member to this forums leads me to believe that you're relatively new to the m10s. Stick around with it, its worth every second/penny in my opinion. This little issue will get resolved with all the knowledge available here.

How is the idle? What about accelerating from a stop in first few gears? That can point in the right direction as far as where to search for the culprit. The box I told you about is called Idle stabilization relay and injectors are grounded though it (at least thats what I have read). If I am correct, and the relay is defective so works intermittently, it would make sense for the jerking and loss of power as the ground is lost during the episode of idle stabilization relay malfunctioning.

[Acet]

To my knowledge, it should NOT be continuously clicking. If I am thinking correctly, it can click as a functional relay does as the pieces inside move accordingly but not just click sporadically on and off for no reason

[Graebmw95]

Loss of power or Misfire at 4k RPM?

Also, seeing that you're a new member to this forums leads me to believe that you're relatively new to the m10s. Stick around with it, its worth every second/penny in my opinion. This little issue will get resolved with all the knowledge available here.

How is the idle? What about accelerating from a stop in first few gears? That can point in the right direction as far as where to search for the culprit. The box I told you about is called Idle stabilization relay and injectors are grounded though it (at least thats what I have read). If I am correct, and the relay is defective so works intermittently, it would make sense for the jerking and loss of power as the ground is lost during the episode of idle stabilization relay malfunctioning.

Yeah I love the m10 and i would love to turbo it but I don't know where to begin with that. Thats why I kind of want an m20 and to buy kamotors kit! Lol!

Sense I fixed my broken wire it idles from 1-1.5. It only idles at 1.5 sometimes and and most of the time at 1.1. I also feel like i've lost a lot of low end. In the first couple gears it feels real sluggish and sad.

And thanks for the help! Means a lot haha

It also only does it at 4k rpm. Not during an idle at all. :/


Sent from my iPhone using Tapatalk

[Acet]

Yeah I love the m10 and i would love to turbo it but I don't know where to begin with that. Thats why I kind of want an m20 and to buy kamotors kit! Lol!

Sense I fixed my broken wire it idles from 1-1.5. It only idles at 1.5 sometimes and and most of the time at 1.1. I also feel like i've lost a lot of low end. In the first couple gears it feels real sluggish and sad.

And thanks for the help! Means a lot haha

It also only does it at 4k rpm. Not during an idle at all. :/


Sent from my iPhone using Tapatalk

Some people like turbo, some say just swap larger motor. Guess its really your choice cuz you're the one to drive it :)

Alright so your idle is fluctuating between 1100 and 1500 rpm? That indicates a vac leak most likely. If I was you, id start by going thought all the vac lines to make sure there are no cracks or possible leaks. Of course a smoke test would be ideal but visual can yield good results too. Also inspect the intake boot which connects from TB to AFM. Many recommend replacing it because it can leak vac.

Even if this vac inspection/replacement wont fix the problem, you'll eliminate possible future headaches and will be able to continue addressing the issue. I know that the Vac advance unit (round metal pancake looking thing attached to the dizzy with a vac line from it running to the square electrical valve on the firewall) is responsible for advancing/retarding timing to compensate for low power in low gears and revive the motor a little. if you say the car is very sluggish even from the get go, maybe it makes sense to look into that.

Read around in this section on M10 vac rerouting options and ICV delete if you're interested. Some go after a "complete" motor but some delete icv and that electric valve for vac advance to eliminate idle issues and so forth. I, personally, had amazing results when I removed some things and unneeded plumbing from the motor. you then just adjust the idle via TB screw and all is great. Anyways sorry if this is getting long, but start with vac system to make sure its functional.

Also, with car running, unplug the AFM and see if the car will idle different. If car starts to run like shit and stalls after afm unplugged, afm is working. Also, see if you can hear the fuel pump priming when you turn the ignition on. You should have two pumps, one in fuel tank and one in front of rear left or right wheel. When in tank pumps go out, car runs like poop too.

[Graebmw95]

Some people like turbo, some say just swap larger motor. Guess its really your choice cuz you're the one to drive it :)

Alright so your idle is fluctuating between 1100 and 1500 rpm? That indicates a vac leak most likely. If I was you, id start by going thought all the vac lines to make sure there are no cracks or possible leaks. Of course a smoke test would be ideal but visual can yield good results too. Also inspect the intake boot which connects from TB to AFM. Many recommend replacing it because it can leak vac.

Even if this vac inspection/replacement wont fix the problem, you'll eliminate possible future headaches and will be able to continue addressing the issue. I know that the Vac advance unit (round metal pancake looking thing attached to the dizzy with a vac line from it running to the square electrical valve on the firewall) is responsible for advancing/retarding timing to compensate for low power in low gears and revive the motor a little. if you say the car is very sluggish even from the get go, maybe it makes sense to look into that.

Read around in this section on M10 vac rerouting options and ICV delete if you're interested. Some go after a "complete" motor but some delete icv and that electric valve for vac advance to eliminate idle issues and so forth. I, personally, had amazing results when I removed some things and unneeded plumbing from the motor. you then just adjust the idle via TB screw and all is great. Anyways sorry if this is getting long, but start with vac system to make sure its functional.

Also, with car running, unplug the AFM and see if the car will idle different. If car starts to run like shit and stalls after afm unplugged, afm is working. Also, see if you can hear the fuel pump priming when you turn the ignition on. You should have two pumps, one in fuel tank and one in front of rear left or right wheel. When in tank pumps go out, car runs like poop too.

I saw a bunch if threads on deleting the icv! I'll definitely look into that.

I'll check all those things and see what i come up with, i'n hoping its an easy fix but you never know! I'll post pictures and keep the thread informed. I have a small list of things to check

1: idle stabilizing relay
2: ecu/ ecu connection
3: vac lines
4: intake boot connections from to afm
5: vac adv unit


Anything els I should really look for?

Thanks again~


Sent from my iPhone using Tapatalk

[Graebmw95]

Update: It's now happening at 3rpm too.


Sent from my iPhone using Tapatalk

[Graebmw95]

I believe I found the culprit! Vacuum hose to my fuel pressure gauge thing.. Lol i dont know the technical name. However, it seems to have solved the issue, for now, we'll see how it acts in the next couple weeks. It also seems to be a little bit more responsive so thats good.


Sent from my iPhone using Tapatalk

[thebutterson]

That's a very probable source of your issue, hope your car runs well afterwords. If the car is new to you then you should probably go through and do all the regular check up items: valve adjustment, timing, fuel filter, air filter, and you may want to consider cap, rotor, wires, and plugs.

[Graebmw95]

That's a very probable source of your issue, hope your car runs well afterwords. If the car is new to you then you should probably go through and do all the regular check up items: valve adjustment, timing, fuel filter, air filter, and you may want to consider cap, rotor, wires, and plugs.

Yeah. It didn't fix a thing. It seems to hate hot days. I have new filters, but cap and rotor should be done.


Sent from my iPhone using Tapatalk

[Graebmw95]

Okay~ so Lets take a look at my plugs, cap and rotor shall we?

Reading from my Haynes manual i can see i'm running way too lean. These are all the plugs in order from cylinder 1 to 4.

1:

2:

3:

4:

Haynes manual:

Cap and rotor: you can see corrosion inside the cap and cracks and burn marks on the rotor. -






Sent from my iPhone using Tapatalk

[Smelser]

TUNE UP!

also, try advancing the timing. If it is too far, it will ping. If it is too retarded it fall flat.