Running Horridly....

[Omaliyo]

Ok well my car was running like ish due to a cracked intake manifold (at least i thought)..... Soooo that gets changed..... and it stills runs like ish.... The car when started (cold) will want to die (i don't have to press the gas to keep her on) I try to take go hit around 1500 and the car is bug like nuts and not want to go anywhere (this only happens when the car is cold).... But what i have noticed is that if i keep the car up in RPMS till warmed up it will run fine.... when fully warmed while going down the road the car seems like its cutting out or something but only for a split sec while at a constant speed..... the car also is extremely sluggish when trying to launch....

What i think might be the problem is a stud in the valve cover cross threaded and the bolt didn't get to torque all the way down...

and my exhaust is completely roasted out and a hole is in front of the O2 sensor.....

Model: 1985 325e

Oh also the car seems to run real well at a quarter tank but at full not so well and when getting to empty runs like shit....

[bebop]

My brothers E did the same thing, he didn't have the resources to really go fix it he thought it was because of the cracked exhaust manifold and it eventually worked itself down to having like 5 horsepower it could barely move itself. Its interesting to hear it might not have been the manifold. My understanding was exhaust back pressure was critical to the car could it be that hole in front of the o2 sensor thats still pretty darn close to the engine. Not an expert just have some experiences with this problem.

[blocke]

My car had a similar problem, though not as severe. If it runs like crap while cold, its usually a suspect coolant temp sensor. The DME runs off the coolant temp till the cars warmed up and switches to the 02 sensor. Mine would idle very low/die untill it was warmed up. Swapped in a new coolant temp sensor (takes less than 5 min, and its $7 bucks from pelican). Car idled and ran like a champ after that, with no warm up time.

Though I would imagine that the hole before the 02 sensor is bad for both backpressure and 02 readings.

[lennon]

Ok well my car was running like ish due to a cracked intake manifold (at least i thought)..... Soooo that gets changed..... and it stills runs like ish.... The car when started (cold) will want to die (i don't have to press the gas to keep her on) I try to take go hit around 1500 and the car is bug like nuts and not want to go anywhere (this only happens when the car is cold).... But what i have noticed is that if i keep the car up in RPMS till warmed up it will run fine.... when fully warmed while going down the road the car seems like its cutting out or something but only for a split sec while at a constant speed..... the car also is extremely sluggish when trying to launch....

What i think might be the problem is a stud in the valve cover cross threaded and the bolt didn't get to torque all the way down...

and my exhaust is completely roasted out and a hole is in front of the O2 sensor.....

Model: 1985 325e

Oh also the car seems to run real well at a quarter tank but at full not so well and when getting to empty runs like shit....

haha why are you ''launching'' this car?

[Omaliyo]

thanks for the info guys.... anyone think that the Temp Switch (P# 12631279722) could be causing this??? mines going bad, at least i think it is.... my coolant temp sensor is brand new.... sooo don't know about that.... I got a new exhaust system (magnaflow 23533 & Bav auto stock replacement) with a new O2 sensor.... so when installed next week it will help....

-Thanks

[DmcL]

fix the hole before the O2 sensor first of all then see what its like. could also have a vacuum leak or 2 somewhere around the intake elbow, ICV pipes, brake booster lines, etc.

[Cyrix2k]

fix the hole before the O2 sensor first of all then see what its like. could also have a vacuum leak or 2 somewhere around the intake elbow, ICV pipes, brake booster lines, etc.

Agreed, but considering it doesn't run right when cold (open loop - no O2 sensor involved), I doubt this it. A vacuum leak sounds much more likely. Also check the coolant temp sensor & cold start injector.

[Omaliyo]

Alright well i changed my exhaust and new O2 sensor are in.... nowwww my car still runs like shit when cold unless i keep the rpms up.... also I've noticed that when cruising at a constant RPM my car all of a sudden feels like it gets pulled on by something and my car starts to cut out or something along those line.... I let off the gas or slam on the gas and it goes away.... oh did i say before i have fuel pops while going slow in maybe 2 gear....

could it be that the gasket between the cold start and the intake manifold is messed up from taking it off to clean and what not....