No Boost

[rwk_stung]

Happy Saturday everyone! Been enjoying my JB4 (w/ Denso sparkplugs) + BMS intakes so far, and have been playing around with various maps (running 93-e30 for fuel). However, I've noticed the last 24 hours that my car will simply not generate boost SOMETIMES. No intake noise, no power. Car feels to be in some sort of limp mode, but no codes thrown or CELs. Problem seems to resolve itself after shutting car off and leaving it for a minute, cranking it back up and going. Does not happen all the time, either- it feels random. I'll crank car, let run a minute or two and take off, it will start to build boost but then I'll come to a stop and start again but then no boost is being built.
Took some logs, could somebody take a look and advise on what could be happening here? Car seems to run absolutely fine otherwise, and it does not matter which map I run.

 

[StingertimeNC]

yep, log confirms, no boost...LOL.

Any other mods on the car? what year? later models just overboost sometimes causing limp mode. (2022, 2023 MY) After a restart, goes back to normal for an indefinite period of time.

Things known to cause overboost could be bad or improperly adjusted Blow off valves, catless downpipes, or other exhaust / intake mods. Normal catback exhaust mods and off the shelf intakes, like BMS, or Injen, etc., normally cause no issues though.

Problem could also be too much e85 mixed in with your 93, causing fuel pump issues. If you have stock cats, exhaust and intakes, it's almost certainly a fuel problem. I would try to empty the tank as far as possible, put all 93 octane in, and run that for a while, maybe 1/2 tank, put more 93 in, then run map 2 and see how the car behaves. Take some logs, etc.

The car feels like a dog when it goes into limp mode for sure.

I would get a flex fuel kit so you know your exact mix and can make sure you don't exceed e30, if you are dead set on running e30.

Also add the EWG wires from Burger.

Good luck and let us know what happens.

 

[CraigS]

Where I live, 91 is the highest octane that comes in on the pipeline. The only way to get to 93 is to add ethanol. In that case you would be over e30, but I would expect that to cause maybe rough idle, issues with starting in cold Temps and high fuel trims at WOT, not overboost. Does the 93 pump say ethanol free? I'm guessing that all varies by region, maybe it is.

 

[StingertimeNC]

It may not be overboost, in the event it's a fuel issue, it actually might be the fuel pump crashing.

I run WMI so not totally familiar with Fuel issues, so we need someone to chime in. Essentially if there's too much e85 in the tank, the system crashes, also causing limp mode.

at least that's what I think....

 

[rwk_stung]

The 93 has up to 10% ethanol in it and our e85 is 57-83% ethanol. I usually do 3-4 gallons of e85 and finish with 93. Hadn't had issues with that till Friday night, and I filled up with 93 after noticing it, meaning I should be a much lower ethanol count now. I'll run just 93 a while and see what happens.

Also I do have the EWG fuel wires from Burger already running with the JB4.

 

[G-870356]

You have both EWG and fuel wires? 2 different things.

 

[StingertimeNC]

Do you have fuel wires and EWG wires? Two seperate things, just making sure. Also email Terry at Burger for advice too.

 

[rwk_stung]

Do you have fuel wires and EWG wires? Two seperate things, just making sure. Also email Terry at Burger for advice too.

I definitely have the fuel wires, but I don't think I have the EWG wires actually. May look into purchasing that.
An update: I ran the tank down to E yesterday, and filled up completely with 93. Haven't had any issues the rest of yesterday or today. Fingers crossed I have no more issues

 

[StingertimeNC]

Awesome! Yes, get the EWG wires. Kind of a pain to install but worth it... (Although, may not be necessary if you stick to just 93 octane..

 

[rwk_stung]

Would very much be worth it to me then, I plan on running Flex Fuel kit at some point and optimizing for as much ethanol the stock fueling system can handle, since it provides such a noticeable performance gain to the car.
Drove around some more. 40 miles on the tank of gas and no issues whatsoever. I wonder if it wasn't just bad 93/ethanol causing my issues.

 

[StingertimeNC]

totally agree it was a fuel issue. probably too much e85 uilt up and the ratios got messed up. flex fuel kit and ewg wires and you'll be set!

 

[AdrianG]

Sounds like classic overboost, but it could be the HPFP crashing, as well. My money is on overboost, though.

I would probably be willing to part with my EWG wires for a good price for yourself, if you are interested. Since I changed over to a Lozic ECU I have pretty much no use for them on my JB4.

 

[rwk_stung]

Sounds like classic overboost, but it could be the HPFP crashing, as well. My money is on overboost, though.

I would probably be willing to part with my EWG wires for a good price for yourself, if you are interested. Since I changed over to a Lozic ECU I have pretty much no use for them on my JB4.

I would appreciate that greatly. I cannot DM members yet, would email be ok?

 

[rpoffen]

Where I live, 91 is the highest octane that comes in on the pipeline. The only way to get to 93 is to add ethanol. In that case you would be over e30, but I would expect that to cause maybe rough idle, issues with starting in cold Temps and high fuel trims at WOT, not overboost. Does the 93 pump say ethanol free? I'm guessing that all varies by region, maybe it is.

We only get 91 here in california too (is that where you are?), which is around 9-10% ethanol. I was able to add E85 to get to E30 (have a flex-fuel kit installed to get accurate mix) and run map 4 no problem. Got low 12's with that. I have since switched to straight 91 + WMI on map 7 and am running 11.80.