Author Topic: m42 cutting out at 3300 rpm (Read 3789 times)

individualist · « **on:** May 24, 2006, 05:18:46 PM »

I just bought a 318is about a month ago and am trying to work thru a couple of issues the car has, one of them I'm not sure how to proceed on. The problem is that the engine runs great for about 11 miles ( half the way to work) and then starts missing and cutting out at about 3300 rpm. If I keep the rpm's below that point everything is fine but once I hit that magic spot it goes to hell. What I've done so far is replace the plugs and ignition wire set, wire set was shot but the plugs didn't look that bad. I had a fuel pump quit on me also, replaced that and the fuel filter. I'm open to suggestions, what about the TPS?

thumper3ld · « **Reply #1 on:** May 24, 2006, 05:24:33 PM »

Ignition coils maybe?

asubimmer · « **Reply #2 on:** May 24, 2006, 09:54:40 PM »

got you on this one, its gonna be your crank sensor. Don't ask me how I know

asubimmer · « **Reply #3 on:** May 29, 2006, 02:55:23 PM »

update?

Veritas · « **Reply #4 on:** May 29, 2006, 07:57:58 PM »

oh geeez, i remember this problem in charlie's car. biggest PITA ever

individualist · « **Reply #5 on:** May 30, 2006, 04:52:17 AM »

I'm going to change the vacuum lines and see if that helps. There is some signs of surface cracking on a few of them and one of them is a US standard size that doesn't quite fit tight. Don't want to spend money on parts guessing what is causing the problem so I'll do the hoses and they do need to be changed anyway. I will keep you all informed.

e9nine · « **Reply #6 on:** May 30, 2006, 06:31:46 AM »

Have you checked the TPS and the TPS wires? Mine were frayed at the connector and would cause the car to buck like crazy while triggering a Check engine light. As mentioned earlier it could also be one of the sensors, Crank or Cam. Make sure they haven't backed out.

Good luck.

M42boy · « **Reply #7 on:** May 30, 2006, 08:08:18 AM »

Your vaccuum hoses are probably "hosed" (No pun intended), but I would doubt they have anything to do with your 4200 rpm cutout.
My money would be on the crank or cam sensors.
Check to make sure the wires are still connected as e9nine suggests.

individualist · « **Reply #8 on:** May 30, 2006, 06:10:13 PM »

Thanks for the info guys, I'll do some poking around on the TPS, cam and crank sensors. I'm kinda new to the M42 so I do appreciate all who help me along the way. I can't complain about the car really, I'm the third owner and I only gave $350 for it from a dead guy (long story but true) that kept superb records.

318-is · « **Reply #9 on:** May 30, 2006, 06:56:31 PM »

how do you plan to test the cam/crank sensors buddy?
the TPS is obviously a resistance but what resistances are you looking for on your crank/cam sensors if any?
the only reading iv got is for the crank sensor; allegedly meant to read between 486-594 ohms...?

individualist · « **Reply #10 on:** June 03, 2006, 09:08:52 AM »

Update to cutting out problem. I changed the cam and crank sensors, changed the ingnition coil packs and as mentioned before the plugs and wires. Engine still missing out but seems to be related to increase in temperature (weather) cuz when it's a hot day it starts missing and cutting out right after temp gauge gets into normal operating range like yesterday for example, 90 degrees outside and it started missing at 2800 rpm and this morning it was 62 degrees and it took a while, maybe 15 miles and then it began cutting at 3800rpm. By the way, I get no engine codes and no warning lights come on at all, I'm thinking maybe I've got a bad temp sensor or something along those lines. It seems that engine heat is causing the problem in some way but the dash temp gauge doesn't indicate high temp? I haven't done any tests on the TPS yet but I plan on doing that today.

Author Topic: m42 cutting out at 3300 rpm (Read 3789 times)

Veritas

318-is