Hard stuttering. Bucks like a horse. Need help. $1 to whoever finds the problem firs

[Savagefurai]

My 88 325 has recently undergone a bit of maintenance. When I got her back on the road, she was running great. About two weeks ago I noticed a minor stumble. This stumble progressively got worse until now, and its pretty much undriveable.
When I first noticed it, it seemed to start at around 3k rpm and would not be dependent on throttle position.
When it got worse in the following days, it became apparent that it was manageable when cold but got progressively worse as it came to temp, at which point it became horrible.
Then we come to today, where it is now doing this even at cold temps.

When it happens it feels like its coughing or stuttering at light throttle and a very jerky, hardcore stumble at wot. It will hunt at idle which is generally around 1k rpm.

I have recently replaced the following
Tps
Cps
Afm
Injector harness
Throttle body gasket
Fuel pump
Fuel filter
Fpr
All new relays
Cleaned and checked c101
Tested DME
Blower motor resistor
Evap canister thing behind tps under throttle body
Checked grounds and contacts @ battery

Another issue that may or may not be related is that my #10 and #20 fuse keeps blowing and I have no gauges, power mirrors or blower. Aux fan does work tho...

Any help would be very much appreciated as this is my main transportation and I'm stumped.

Whoever finds the problem gets $1 gifted to their paypal.

Thanks guys.

[delamaize]

according to my bently manual, #10 runs a mess of things, some of the high points are the tach, and other engine vitals gauges, and "fuel delivery system" which is also fuse #9

#20 is the heat/ A/C and aux rad. cooling fan.

If I had to make an educated guess, I'd say you got something in cluster that is shorting out and popping those fuses, and given the "fuel delivery system" is on the same fuses, I'd say you're problem is.

I'm just stabbing in the dark though.

[Savagefurai]

Im pretty sure it isn't a fuel problem because of the parts I have replaced and because I have good pressure at the rail.
I will re check the cluster tho. Any common failures behind there that could be associated?

[Savagefurai]

Anybody got any thoughts?

[dnguyen1963]

Do a smoke test if you are sure that you do not have eny electrical shorts.

[Checkered Sphere]

Check the hoses around the fuel pump and filter and make sure they are not pinched. Had this happen to me after I replaced a filter.

Check for spark at each plug. Did you replace your injectors?

[Killacortes]

This happened to me on two different e30s both had a problem with the ignition coil

[CarsSuck]

This might be a bit of a stretch, but since you've got an '88, I would try to verify that you have the correct CPS and Coolant temp sensors, since there were a few different specs and BMW made lots of changes starting in late '87 thru '89 cars.

You know about the separate coolant sensors, right? single pin sensor is to the gauge and two pin is for the DME. Best way to verify resistance is with an ohmmeter at the temps given in the Bently manual.

[Holland]

I've been dealing with a similar problem on my M10 for months. It's becoming quite expensive...

Good luck, and let us know what you find.

[Savagefurai]

Check the hoses around the fuel pump and filter and make sure they are not pinched. Had this happen to me after I replaced a filter.

Check for spark at each plug. Did you replace your injectors?

I've checked this. Injectors replaced.
I have spark.

Do a smoke test if you are sure that you do not have eny electrical shorts.

A smoke test is on the way if I can't narrow it down.

This happened to me on two different e30s both had a problem with the ignition coil

Coil and dizzy cap are both brand new.

This might be a bit of a stretch, but since you've got an '88, I would try to verify that you have the correct CPS and Coolant temp sensors, since there were a few different specs and BMW made lots of changes starting in late '87 thru '89 cars.

You know about the separate coolant sensors, right? single pin sensor is to the gauge and two pin is for the DME. Best way to verify resistance is with an ohmmeter at the temps given in the Bently manual.

The cps I got was a factory piece and I am picking up both sensors today.

I've been dealing with a similar problem on my M10 for months. It's becoming quite expensive...

Good luck, and let us know what you find.

This^
I have probably dumped close to a grand into this thing.
By the time it does run right, it will be new. Lol.
Thanks tho.

[cgk_iii]

Do a compression test.. Sounds like you're not getting the correct fuel/air delivery. Maybe a leaky head gasket?

[Savagefurai]

Do a compression test.. Sounds like you're not getting the correct fuel/air delivery. Maybe a leaky head gasket?

Maybe, but wouldn't my oil and water be inter mixing?

[cgk_iii]

Maybe, but wouldn't my oil and water be inter mixing?

Lack of engine power is also one of the signs of a blown head gasket. The engine will lack power because of compression loss and the engine will run poorly and have a rough idle. I experienced these symptoms with with my 90 325i before i started seeing water and oil inter mixing. Wouldn't hurt to check!

[Savagefurai]

Lack of engine power is also one of the signs of a blown head gasket. The engine will lack power because of compression loss and the engine will run poorly and have a rough idle. I experienced these symptoms with with my 90 325i before i started seeing water and oil inter mixing. Wouldn't hurt to check!

Alright then.
I will add this to the list.

[cgk_iii]

Good luck! I hope thats not the case