Check engine light
 

Ok this is a long one, and strange.

Info
2017 BRZ
Was tuned on E85 at 1K miles.
AVO turbo with larger injectors and upgraded pump installed around 5K miles.
This has been on for about 2K miles now.
All tuning done by Delicious.
Only anomaly has bee around 3 times since turbo install on start up the MAP is reading 52 inches at idle. A couple of restarts have cleared it. AVO has not stepped up yet to replace MAP sensor.

New problem
Finally took a long road trip just under 300 miles instead of my usual commute of 19. Was able to keep E85 in the tank on the entire trip. After about 200 miles at cruze the engine stumbled/cut out a couple of times. This was followed by a check engine light. However it did not take out the cruze control. This light turned off and back on a couple of times. Pulled off to get gas and no trouble codes were stored. Went to start the car after filling up and it immediately died. Then the next start was good. This issue came and gone a couple more times on the rest of the drive. This also happed a couple of more times while in Austin for the weekend. Along with the engine dying immediately after startup.

Sunday morning getting ready to drive back I hooked up my computer to catch it in the act. On start up this morning it threw a hard check engine light. Codes P0171, P117B, P1170. I cleared the codes and keep the computer hooked up and started driving back. No issues at all after 3 hours or so and 1 fill up. Shortly after computer battery was almost dead so I shut it off. About 15 min later with cruze control on the car stumbled and the check engine light came on. I did notice on my wide band AFR it was jumping from 13 to 17 or so instead of the usual 15 +- .5. This continued for about a min then the light went out and AFR stabilized. Never took cruze control off. No issues the rest of the trip.

I love these intermittant issues that you can not catch in the act.

What are your thoughts? How many issues are there that will cause the check engine light to come on with out killing the cruze control and will clear itself?

DANG, Grady, you're using E-85, you put in larger injectors, you installed a turbocharger, you had it tuned ........ then you head off on a long road trip .... and now you are wondering why the engine is bitching .......?? :iono:

Well, you did ask for my thoughts ..... ;)


humfrz

If you would read it has been installed for 2k miles.
(K means Thousand FYI)

http://www.ft86club.com/forums/showthread.php?t=82274

All the same codes. Was a bad battery. I would check for a poor connection just to rule that out really quick.

As above check battery volts under load

Check DI computer is bolted to engine with all 3 mount bolts thats its ground, it goes nuts if gound is bad

Quite a few MAP sensors fail
Deliceous uses a weird hybrid SPEED Density type tuning on many turbos which relys on MAP (pressure sensor) for fueling not MAF.

Check fuel pressure and fuel pump

and for intake or exhaust leaks

check all hoses including ones under intake manifold clamped

They are the common causes

Thanks for the math/metric lesson ...... :w00t:


humfrz

Battery volts check good.

Will recheck DI computer, it was taken loose during install.

If nothing else is found may just replace MAP sensor.

Have the + flex fuel, should get limp mode if fuel pressure is low.

Do not hear any exhaust leaks will double check.

Manifold pressure is good at idle do not suspect any intake leaks.

Thanks for the info!!!!

Check the ground on the DI computer. More than one have gone by recently having an array of problems and it just was a loose connection.

Ok working with Delicious on some logs it is looking like a fuel pressure issue. Low enough to cause issues intermittently but not take into limp mode 100% of the time. Have to do a couple more checks to verify. Will update after those.

Update. Recieved pressure sensor and tested car. Still was acting weird at idle. Opened up the Delicious app and checked parameters. Fuel pressure was still all over the place however E content was now reading 0.0. I knew this was wrong since I have been on E85 for the pas 8 tanks or more. Worked with Delicious on further troubleshooting and it acted like a possible cold solder joint to me since it had started mild but progressively gotten worse. Got approval to open the D box under warranty and found water ingress. This explains everything now! Delicious does not warranty water ingress however they have made an exception in my case. The new box is also being treated with a hydrophobic coating to help. I will defenatly mount the new box with the wires pointing straight down. May even add sealant around wire harness where it goes into the box. I just assumed this box had at lease an IP rating of 4 or so. Just so you know this box has a rating of 1 at the most.

This is especially important to people with vented hoods. My vents were just aft of the D box but there was enought spray to get into the box.

I can not say enought good things about Delicious in how they handle things! The company has been a pleasure to work with and I will continue to use them for everything I can.

Imagine that ...... you have holes in your car's hood and you had a water in your car's electronics problem ....... :eyebulge: ..... :iono: ...... SMH


humfrz