Do I have bad coil packs or a failing DI pump?

[xkalelx]

I had an event on the highway yesterday. I wasn't logging. Car started stumbling when going into boost. Decided to just use cruise to get home. Car started stumbling on cruise 5 miles later. Total loss of power 5 miles later. Car acted like it didn't have any fuel or wasn't getting any fuel. Threw a CEL as it died. P0087 - low fuel rail pressure. Wouldn't start at all with 3/8 tank of e70. Had some good Samaritans run and get me a gallon of 93. Car started up after sitting for 20 minutes just fine. Drove it to a gas station and put 7 gallons of e85(e70) in, so I know my gas gauge isn't faulty. I got home with no issues. Couldn't diagnose anything wrong in the driveway. Drove it to work just fine this morning. Boosting to 8psi is just fine at e67. What is intermittently failing? Car wasn't overheating. Oil was at 210F and coolant was nominal.

Over the past couple weeks it would give me a light stumble on boost but always drove fine. Starting has become longer. Idle is fine. It backfires a bit in between shifts when cold or hooning. Two weeks ago while on curvy backroads I got a pending CEL for a misfire on Torque Pro but it went away on its own before I could clear it.

Theory 1. I took a high speed left turn to make a light to get on the highway. Is there any possibility that I sloshed all my fuel to the passenger saddle bag and dried up my fuel pump reservoir on a flat highway? Ive had two different shops pull both sides of the tank in the last 4 months. I wonder if something happened to the crossover or secondary pickup.

Whats going on here? Anyone have any insight? I have searched but not finding much for this weird symptom.

TIA
Sam

[GsxrMe]

Use torque pro and watch you fuel pressure. You might have a failing fuel pump.

[raven1231]

Off topic but how are you liking your driven kit? thinking about getting one myself.

[Gear_One_Performance]

Originally Posted by GsxrMe

Use torque pro and watch you fuel pressure. You might have a failing fuel pump.

This, we're lucky enough to have a fuel pressure sensor on the rail stock so it's pretty easy to check the pump.

[xkalelx]

Cool thanks guys! Ill start monitoring that.

Originally Posted by raven1231

Off topic but how are you liking your driven kit? thinking about getting one myself.

Its bloody beautiful. 12psi on ethanol is a blast. Ive had really good luck with component selection and tuning at Dynosty.

[raven1231]

Originally Posted by xkalelx

Cool thanks guys! Ill start monitoring that.



Its bloody beautiful. 12psi on ethanol is a blast. Ive had really good luck with component selection and tuning at Dynosty.

Appreciate it man! I plan on going to Dynosty too if I go this route. How long have you had the kit?

[xkalelx]

Originally Posted by raven1231

Appreciate it man! I plan on going to Dynosty too if I go this route. How long have you had the kit?

Since October. Just working out all of the bugs now. Its a really solid kit and very fun.

[CSG Mike]

Do you have an aftermarket in-tank fuel pump?

The fuel rail pressure low code is specific to the DI rail, post DI pump, and fuel starvation can cause it.

A failed DI pump will have noticeable other symptoms.

[xkalelx]

Originally Posted by CSG Mike

Do you have an aftermarket in-tank fuel pump?

The fuel rail pressure low code is specific to the DI rail, post DI pump, and fuel starvation can cause it.

A failed DI pump will have noticeable other symptoms.

I do, it is a DW300 feeding DW700 ports. All DI is stock obviously.

[CSG Mike]

Originally Posted by xkalelx

I do, it is a DW300 feeding DW700 ports. All DI is stock obviously.

How hot was the weather it when this happened? Is it possible your electric fuel pump overheated, causing your mechanical pump to starve? I've seen it happen when driving for long periods of time.

The code you saw only gets thrown when there is, literally, zero pressure in the DI system.

[xkalelx]

Originally Posted by CSG Mike

How hot was the weather it when this happened? Is it possible your electric fuel pump overheated, causing your mechanical pump to starve? I've seen it happen when driving for long periods of time.

The code you saw only gets thrown when there is, literally, zero pressure in the DI system.

70 deg ambient. I wasn't even fully warmed up yet when it first hiccuped. I dont see it being a likely culprit but I wont rule it out. Come to think about, the few times it has stumbled under boost, I have been below a half tank. I wonder if that has anything to do with it. I see me pulling both side of the tank this weekend to inspect. If for some reason the driver side saddle of the tank is running dry I would expect this to act like I was running on fumes. It literally acted like I was running out of gas, steadily getting worse.

[CSG Mike]

Originally Posted by xkalelx

70 deg ambient. I wasn't even fully warmed up yet when it first hiccuped. I dont see it being a likely culprit but I wont rule it out. Come to think about, the few times it has stumbled under boost, I have been below a half tank. I wonder if that has anything to do with it. I see me pulling both side of the tank this weekend to inspect. If for some reason the driver side saddle of the tank is running dry I would expect this to act like I was running on fumes. It literally acted like I was running out of gas, steadily getting worse.

Which line is your FF kit on?

Try to grab a log of it happening again, and I'll take a look. I've seen similar issues on other cars, and as it gets worse and worse, and happens more and more, we've been unable to figure it out. Some cars it never happens again, some cars, the owners just give up because nobody can figure it out.

I'd like to add to that data set.

[xkalelx]

hmm... Fuel pressure at the rail looks good. Was running great. Ill keep monitoring it. @CSG Mike





Here is what I am thinking could be the culprit right now. It has only stumbled after Dynosty pulled both the pump and pickup from my tank to evacuate 93 for a e85 dyno session. I think what could have happened was this pickup line either become disconnected by accident or not plugged back in. I will investigate further.

[xkalelx]

Originally Posted by CSG Mike

Which line is your FF kit on?

Try to grab a log of it happening again, and I'll take a look. I've seen similar issues on other cars, and as it gets worse and worse, and happens more and more, we've been unable to figure it out. Some cars it never happens again, some cars, the owners just give up because nobody can figure it out.

I'd like to add to that data set.

My FF sensor is on the main fuel line, and has been for over a year. I just switched from Delicious to MotoEast but the lines and sensor are still the original from Delicious.

I will definitely grab some logs. Ill try to provoke the behavior later this week when my tank gets around a 1/4 full. Thanks for the help man!