I need some help please! bad idle

[jdean41]

So i posted earlier about an ideling problem i was having. Cleaned my iacv, adjusted valves, cleaned my throttle body and check my timing and nothing worked. So when i was adjusting my valves i finished up and fired her up and took her down the road. It was a huge help, but when it got warm it started ideling really rough as usual. I got back home and popped the hood and noticed that it sounds like its not making quite the amount of oil pressure it should to idle smoothly. The car was converted to a 5 speed and it has a "tuned" ecu. I think when they messed with the ecu it screwed up my oil pressure, or it still has the original ecu from when it was auto and they just put it on a machine and screwed it up. Do i need to go ahead and swap it out for a stock ecu for a manual trans???

 

[Prozon]

I didn't think you could effect oil pressure by tuning. The oil pump turns by the timing belt.. there's no much you can change about that set up.

Is it idling up and down, or rough? Whats the deal?

 

[TwistedFate]

If you think it's an oil pressure issue then maybe your lines are a little clogged with sludge. If you do regular oil changes about every 3k miles or so you shouldn't. You can always add in some seafoam with your oil to clean it out. Put like 1/4 to 1/2 of the seafoam bottle in, drive 100 miles or so and do an oil change.

If it's a shaky idle check the motor mounts and make sure they're tightened down.

Could be something with suspension as well but I don't know much about that.

 

[BrokenTalon27]

Need more info on the ECU...also, the ECU would not be a direct effect of low oil pressure. The oil pressure is a mechanical process driven by the cog on the oil pump that is turned by the timing belt, not a direct ecu controlled function.

 

[jdean41]

My ecu was quote "tuned" to redline at 8000. And i think it was messed up. Im almost positive that its oil pressure because you can basically hear it. When it gets completely warm it idles really rough fluxuating between 1000 and nothing basically. Its cut off on me 2 times. Most of the time it will start getting rough and i can pat the gas and it will steady for just a second and start again. Idk. Im probably gonna change my oil pump, timing belt, water pump and everything this weekend when i service it.

 

[BrokenTalon27]

Try cleaning the IAC and FIT valves. I dont think your oil pressure is the cause. Also, get a good tuner to retune the ECU.

 

[jdean41]

Already did. I pulled my throttle body, iacv and everything and checked them out and cleaned them. If its not my ecu causing it its probably my oil lines being clogged or something because everything else has been checked and checked over multiple times. Im going to put a stock manual trans ecu in and c what it does and if that works im going to take it and have it professionally chipped and tuned.

 

[TwistedFate]

Drop out your alternator and get it tested. I've been having some idle/power issues with my 90da9. It has rpm spikes at night when my lights are on or when I'm using any other power source other than basic motor function. But I'm getting a new wiring harness and having my alternator tested this weekend.

 

[jdean41]

its got a brand new alternator in it lol And it doesnt do anything like that. None of the electrical stuff effects the idle. It does it regardless. Im going to pick up some oil treatment tomorrow and run it through and c if one of my lines might b partially clogged because u can hear basically hear that theres not enough oil pressure when its ideling. If that doesnt work im swapping the ecu and going from there.

 

[Prozon]

How do you hear there is no oil pressure? I didn't know you could hear that kind of thing.

 

[jdean41]

When an engine is ideling really low like that and really roughly if u listen close enough u can almost hear the pressure. No oil pressure means no run lol. My uncle is the one who thought that might b a reason. And he knows. Hes a certified mechanic of about 25 years and has seen everything. Idk im gonna pull my fuel rail and injectors in the morning and check them and make sure im good in that department.