Problems with starting, acceleration
I have the 400 hp system with the fitech electric fuel pump. I have it on about a month. Maybe 500 miles. It wa running ok, but not so much anymore. I had a problem where after being parked warm for ~ 40 minutes it would barely start and run for the first two minutes. I called Fitech - they said to make sure the white wire had 10.5 v at crank. I took it back to my mechanic. He put a relay in, and got it the most voltage he could. I have not had a chance to test this out. Before I took it in, it had been falling on its face when accelerating cold - stalling twice.
Today on the way home from the shop, it has two problems:
warm start is terrible. I have to hit the throttle a few times to clear it. Second problem is that when you accelerate from a stop, or cruising speed, it bogs down. The afr shows around 10 with no AFR adjustment. After spitting and coughing a while the afr goes to 13ish and it runs ok. The repeats ever stop/accelerate.
I called Fitech - they had me check the fault codes. It had an rpm noise code (P0335). The fitech rep said it was caused by noise. He said I could wrap the blue wire in aluminum foil, or get EMI/EMF tape. I tried the foil. Same problem. When I went to call fitech back, they were closed. I'm getting pretty frustrated with this - it is not reliable at all. I emailed their support - and will probably hear back Monday or Tuesday. I am tempted to do a reset, but I don't know if that will do anything.
Any advice?
Your issues are not from a the Fitech. They are from poor installation and poor tuning. Did you have someone else install this?
How can you determine it is not a fitech issue? Yes I had it installed. They did a good job. Very neat installation. Welded in a bung for the o2 sensor. The unit tunes itself. It is setup correctly.
Quote from minagle on May 4, 2019, 5:34 pmHow can you determine it is not a fitech issue? Yes I had it installed. They did a good job. Very neat installation. Welded in a bung for the o2 sensor. The unit tunes itself. It is setup correctly.
I can determine that from diagnosing this issue many times. The unit cannot self tune its way out of electrical interference.
We can help, but you will need to be patient and be willing to learn a lot.
Let's start here. What is the vehicle, engine, cam specs, etc. Also send some pics of the engine bay.
It’s a brand new Chevrolet performance 290/350. Cam specs are
- Camshaft Lift (in.): .450 intake /.460 exhaust
- Camshaft Duration (@.050 in.): 222° intake / 222° exhaust
setup is for cam is 2.
1982 gmc pickup.
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He'll yeah, Square GMC. Right on....
See how your blue wire wraps around your plug wires and looks to be touching a plug wire. That will definately create interference.
When you get the interference cleared up. I want you to Datalog a 30 second log at idle and above 170 degrees coolant temp. There are plenty of videos to show you how to Datalog if you need help. Then post the log here.
To post a log, you must use Dropbox to share the file. Dropbox is a file sharing app that is free. Hook your handheld to a pc or laptop and find the datalog. Copy file to Dropbox, select 3 dots on right of file name, select share, create link, copy link and paste to a new post.
We will have you going in no time. Just need to see the general health of the setup first.
What’s the best way to get the interference cleared up?
Thanks for the help
Move the blue wire first....
I moved the blue wire away from all the spark plug wires. Took it for a test drive. Seems mostly cured. Sometimes it hesitated when accelerating when cruising. I did log on from the dashboard for thirty seconds at idle. Then did log off. Hooked it up to my computer and there is no log folder. Also the rpm noise code did come up again, but the engine is running better. I’ll try starting it again in a little. I’ll attach the updated wiring.
What am I missing with the data log?
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That's great. We just wanted to solve the interference issue. That is done.
Driveablilty is a few steps later.
A common issue with new users is getting use to the fact we have data. With carbs all we had was seat of the pants, so many will make a change and then drive. Not necessary for Fitech. A lot of time can be saved by tuning to the data right there in the driveway.
When datalogging make sure to turn key off and let the ecu power down. Can be seen when watching dashboard and data blanks out. This hard saves the datalog. Then unplug handheld and take to PC.
Datalog will be within log file/dashboard file. If no log is seen, delete the dashboard file folder. This folder will generate again when another log is saved. Do not delete log file. That one does not generate.
This is a little glitch that has not been remedied by Fitech. We have all learned to delete the file folder instead of the individual files.