Eta hesitations. Slightly puzzled-

[Ark]

When I bought my e30 (87 325e) , the previous owner had taken it to have an exhaust put on- and the shop just cut the 02 sensor wiring, tacked together a really poor system and sent them on their way. I recently put an exhaust on, and bought and 02 sensor, wired it up, and the idles right again! However it's picked up a hesitation below 2500 rpm. Full throttle, above 2500, pulls like it's suppose too.

already has,
New Cap/rotor/plugs
fuel filter
Had a vacuum leak at the intake boot a few months ago, replaced that, as well as all the hoses to the ICV
Threw a new coolant temp sensor in today, to see if it helped (it didn't)
Prolly some other stuff I'm forgetting-

If you unplug the 02 sensor though, Idle moves to 1100, and the hesitation is gone. What am I missing?

[Bimmerboy91]

How does it act when it is cold?

Perhaps you have a faulty oxygen sensor causing it to do that.

[Kershaw]

Personally, as a rule of thumb, if I unplug a sensor and an issue goes away, I replace that sensor. It's not always the solution, but I think it's generally the place to start.

[Ark]

Runs the same cold as it does warm, I guess it's just as likely i got a bad sensor. Wondering if the TPS could be causing some of this.

[jeffnhiscars]

Tps is only active at idle and wot. If the problem occurs only midrange you can eliminate it as a cause of this problem

[skunka]

same problems

Not trying to thread jack, but first time poster with similar problems....

My PO cut the O2 sensor wire and i think completely removed the o2 connection that goes to the DME. I really need to sort this...

Similar problems. Car idles very nicely, but encounters problems between 1500-2000rpm. Gets all sputtery and hesitant. Engine sounds great from 2500-WOT. I don't know if its from the engine running rich or not. I recently replaced intake boot and some other vacuum lines and seemed to help quite a bit.