Car is stalling on start after Intake+header and a tune install.
 

Hey guys, I'm currently working on my GF's car to get it a bit more power, but I've run into this issue and I can't quite figure out what's going on. I'll admit this build has had more issues than I expected as I ran this same setup on my car prior to boost.

1. Installed JDL UEL (Catless) Header
2. Installed Grimmspeed Intake
- Started car, everything seemed good, no leaks that I could smell.
3. Loaded Stage 2 Flex tune from Delicious
- Fuck up #1. The car didn't have the flex fuel kit fully installed as I ended up with the wrong sensor for the Dbox. So I left the stock rear O2 plugged in but apparently needed to have that unplugged.
- Went to the gas station, car behaving a bit weird. After getting gas it refused to start, Idle-sputter-die, ad nauseam. Towed back to my house and Bill got back to me letting me know I fucked up with the rear O2 as the car was looking for ethanol content that wasn't there. Unplugged it and it started and ran great. :bonk:

NOW here's the thing - Entirely random, hot, cold, warm, whatever it will refuse to start a few times in a row. If you're persistent, taking the key out etc. It will eventually start and act like nothing happened. When got logs of this happening my tuner said the Front O2 sensor was not working for some reason. When I got logs of it running, he said everything looked great and on point.

Since then, I have
- replaced both the Front and Rear O2 Sensors (Rear was replaced during the header install due to stripping)
- Flashed the non-Flex Stage 2 tune from DT
- Installed the full Flex fuel kit
- Reflashed the FF Tune
- Followed the relearn Idle guide sent to me by Bill.

Just this morning after everything went smoothly while installing the kit and relearning idle last night my GF said it stalled again for her while trying to leave for work. (For clarity sake, the car is running and has run on 93 only.)

For the life of me I can't figure this out... help. :iono:

If your on petrol , id flash a complelty stock tune to car and see if you still have peoblems. Just disconnect flex kit from rear 02 sensor and plug sensor back in.


Stock tune should run fine with grimspeed intake and catless header. You might trip P 0420 cel re cat efficiency and cruise control wont work. But car should not stall or thow other codes unless theors some hardware issue.


Make sure the maf sensor cable is plug in all the way. Check the DI computer has all 3 bolts tight. Check for intake leaks. Check both 02 sensors p!ugged in


When you say refues to start does engine crank ? Or no cranking

Sorry, that's my bad on word choice - The car starts but then immediately dies within about 2-3 seconds.

Check fhe DI computer is plugged in and is groumded via its mount bolts

is it only when cold? when the engine is hot does it cut out after start up? could be a weak battery/alt thing with bad spark..

It's entirely random. Can happen in the morning, afternoon, hot or cold, though usually in between.

I'll give that a check though I can't imagine they are. They've never been touched.