M50: Bad idle when TPS connected

[lolcantturn]

I'm a 100% noob at the M50 motor, but I think I have all the vacuum lines attached right.
The only thing not on is the charcoal canister, the lines to it are hanging freely and the purge valve isn't connected
Certain times when I'm just idling, the car will momentarily die and then the idle picks up at :05, I was lucky to catch it on video.
I know I have an exhaust leak before the O2 sensor.
Also have a check engine light. Not sure how to really diagnose this.
The engine is pretty responsive eitherwise.



Any ideas?

UPDATE: I couldn't narrow down any vac leaks but I figured out that if I disconnected my TPS my idle greatly improves. But I can smell the richness my engine becomes. Any ideas?

[matt]

You can stomp test the CEL.

Hit the gas pedal all the way to the floor then all the way back to zero five times after keying the car on (don't start it)

[lolcantturn]

Stomp test didn't work :/

[cabin]

You said the charcoal canister isn't connected, do you have the port on the throttle body plugged? If not, there is one vacuum leak...

[matt]

Stomp test didn't work :/

It's tricky.

[Jand3rson]

You said the charcoal canister isn't connected, do you have the port on the throttle body plugged? If not, there is one vacuum leak...

I noticed mine wasn't plugged right before I mounted my throttle body up (no charcoal canister on my swap), and I just stuck a little black vacuum cap over it, you'll definitely want that port either plugged or connected to the canister.

[lolcantturn]

You said the charcoal canister isn't connected, do you have the port on the throttle body plugged? If not, there is one vacuum leak...

Port is plugged there

It's tricky.

Trickier than M20? I could get the stomp test to work on the M20, but I can't for the life of me get it to work here. Mine is a NV motor if that helps

I noticed mine wasn't plugged right before I mounted my throttle body up (no charcoal canister on my swap), and I just stuck a little black vacuum cap over it, you'll definitely want that port either plugged or connected to the canister.

It's plugged :/


Like it's not even that my idle is crazy unstable, the engine literally shakes the car on idle, and I'm on decently soft E34 mounts

[lolcantturn]

One other piece of info: I'm running my friend's NV ECU which I think may be setup for a lightwheel flywheel, he doesn't know if it is either. Maybe that's contributing to something?

Something I noticed was, if I'm cruising around town at lets say 1500rpm, and I come to a stop, my idle will be PERFECT. Then it will die and pick up (like in the video) except the idle will be fucking terrible.

[trackjunkie21]

One other piece of info: I'm running my friend's NV ECU which I think may be setup for a lightwheel flywheel, he doesn't know if it is either. Maybe that's contributing to something?

Something I noticed was, if I'm cruising around town at lets say 1500rpm, and I come to a stop, my idle will be PERFECT. Then it will die and pick up (like in the video) except the idle will be fucking terrible.

It's a vacuum leak, I'm having a similar problem right now. Just started today =/

[lolcantturn]

It's a vacuum leak, I'm having a similar problem right now. Just started today =/

Shit sucks, driving me kind of nuts haha.

[trackjunkie21]

Shit sucks, driving me kind of nuts haha.

Does the car feel like it has no power under load?

[lolcantturn]

Nope, runs strong as all hell.

[M-technik-3]

One other piece of info: I'm running my friend's NV ECU which I think may be setup for a lightwheel flywheel, he doesn't know if it is either. Maybe that's contributing to something?

Something I noticed was, if I'm cruising around town at lets say 1500rpm, and I come to a stop, my idle will be PERFECT. Then it will die and pick up (like in the video) except the idle will be fucking terrible.

Let me get this straight your engine is a m50b25tu yet you are running a m50b25 ecu? I would say that alone is part of of your issue.

When you drove to gutten which ecu did you have? There was no mention of issue then.

[mr2peak]

Do you have a lightweight flywheel? Mine surges at idle when the A/C or heater is on. Most afermarket chips that are set up for a lightweight flywheel raise the idle to get around the problem. Your idle s pretty low so I'm guessing it's not a lightweight chip.

[lolcantturn]

Let me get this straight your engine is a m50b25tu yet you are running a m50b25 ecu? I would say that alone is part of of your issue.

When you drove to gutten which ecu did you have? There was no mention of issue then.

nooo my M50 is NV as well. And I used that same ECU, my idle problem was still there but I thought it was cause of the torn-to-shit intake boot, which I replaced

Do you have a lightweight flywheel? Mine surges at idle when the A/C or heater is on. Most afermarket chips that are set up for a lightweight flywheel raise the idle to get around the problem. Your idle s pretty low so I'm guessing it's not a lightweight chip.

Come to mention it my friend's M50 with the ltw flywheel idles at like 900rpm while mines pretty low