goneboating06

So i have been having a idle issue with the wonderful renix system we know and love so much

What happens is it starts fine (it misses a bit, but overall its smooth) and then after a while (about 33 seconds in the youtube vid ^^^) it will act like its going to die, and then catch itself, and then do that over and over until i drive it for a while and the engine is at operating temp. The idle is also jumpy and inconsistent all the time, especially when its cold.

Replaced List:
O2 Sensor
Map sensor
CTS
Knock Sensor
TPS (adjusted)
IAC
Neg. Batt Cable
EGR Valve
CPS
Neon 703 injectors with new o rings, filters, and ultrasonically cleaned

Checked list:
MAT (good... at least at room temp it is)
CTS (good... at least at room temp it is)
ICM contacts cleaned at connectors and coil clips
All my grounds are clean/ new (showing around .2ohms)
Soldered in a extra ground wire at engine wiring harness just to be safe
NO VAC LEAKS!!!!
As far as i can tell the EGR is working.


My engine was rebuilt around 15K ago, and when i rebuilt it i cleaned the TB and intake manifold inside and out to new condition. It was having this weird idle issue even before i bought it. Its just gotten worse over time.

Question: Could the computer be the cause of this problem? yesterday i was bored so i took the computer apart and i couldn't tell that anything was loose, or burned, or i dunno... i didn't really know what i was looking at or for, i'm no computer genius haha.

Also would a FPR cause problems like this?

Please help, otherwise my jeep runs great, its just kind of frustrating, and its getting worse as the weeks go on.

The Rooster

Does your Jeep have the c101 connector???

goneboating06

No it doesn't, its a earlier 89, actually built in 88.

The Rooster

the c101 connector ran from 87-89 just a fyi .... and can you take a video of your motor running from under the hood... that would help a lot more...

goneboating06

Oh i didn't know that... i just thought it was on the late 89's and 90's. Anyway, yeah my jeep doesn't have one. Ill go take a video of it running under the hood right now.

goneboating06

Here is the under hood idle video

>>>> <<<<<

Just a note: At the time this video was filmed, the engine was at operating temperature... so the idle is smoother then when its cold, but its still jumpy. Also my jeep has a sick sense of humor, so of course its running better then normal at the time i need it to run like it normally does...

89whiteXJ

Renix seems to always have that sick sense of humor. They are good one min and crap the next. Its the beauty of Renix.

goneboating06

Haha gotta love the good ol' renix

The Rooster

exhaust sounds nice... i hear a small vac leak from somewere on your drivers side.... also check your exhaust manifold... see if it has any cracks...... sounds very healthy tho... is it all stock..? very nice and clean

goneboating06

Ill re check for vac leaks. I am 90% sure there isn't any as i have checked literally over a dozen times haha, but thats not to say i haven't missed something. In the video i set my phone down by the intake, so that may sound like a vac leak, also my PS pump sounds like one. But my exhaust manifold was cracked when i rebuilt my engine, so i took it in to a very skilled welder, and he welded it. It was only meant to be a temporary fix as i was limited in funds at the time. The welder thought that it would hold up for a long time, however i had my doubts. But it seems to have held up very nicely so far. So when it cracks again ill replace it. But as far as the engine goes its all stock. The only "mods" that are done is all the paint, the neon 703 injectors, and my pistons are .040 over. But thanks! It was quite the project getting it all nice and clean haha