Fuel injection GO-EFI FITECH

[Marcus]

Hi all,
Struggling with a USA built GO-EFI FITECH on my reasonably stock road 302. I haven't used a Fuel injection set up before so am wondering if anyone on the Forum has some advise on settings...?
I have a standard looking menu however at the mo it's mostly Greek to me as I don't know what settings I should be possibly running...
Right now engine struggles to pick up smoothly at lower rev range and it's only around 3.5k when things seem a little better....
The plugs are very wet and with the smell indication is that the mix is too rich although the engine symptoms act like it's running lean...
Not sure if any US chums out there are ru nine or of these injection systems but would sure appreciate some advise on what is considered base line settings for a 302 so I can ensure my setting are where they should be on the menu...
I adjusted the plug gaps to around .035" to.040" running slightly cool plugs and am running an MSD dizzy....
Thanks in advance for any help guys.
Cheers
Marcus

 

[Ian Anderson]

Hi
is this on a GT40?
does it have slip on headers?
is O2 Sensor rear of these slip on connectors?
if so my immediate thought would be it is sucking in air and this causes the sensors to read low and say to add more fuel.

bit it is a bugger to seal fully the headers

And as you say at higher revs it smooths out…..by then not enough time for it to suck in air.

Ian

 

[Marcus]

Hi Ian... very kind of you to respond...
Yes it's a GT40 Replica... has bundle of snskes headers and the O2 sensor is located in one of the collectors between headers and silencer.
The car has been unused for some time and I am not sure if the fuel injection system has defaulted to factory setting...??
Maybe there is too much air as you kindly mention and I will try to check collector unions and seal as I can see some traces of exhaust gas.
I might contact manufacturer to see if they have a stock 302 set up... hopefully I will get her running right...
Thanks for the advise..

 

[Joel Heinke]

I second Ian's suggestion that the symptoms sound like a false reading from O2 sensors. I have an LS powered car (so GM style EFI) that has had similar symptoms since I have started driving it. I had a full dyno tune done on it prior to putting on the street, so I'm fairly certain the tune is not way out of whack. The main thing in common with your described situation is O2 sensors downstream from an exhaust connection, in my case it's V band connections at the collector to head pipe. The current O2 sensor location is a couple of inches downstream from the V bands. My latest attempt to fix was adding a bunch of high heat silicon at the V band connections. After this change, it runs much better (smoother acceleration and more power in the transition from low to mid range rpm) but still has symptoms of a bunch of fuel getting dumped in (popping sounds from exhaust) at 3,600 to 3,800 RPM range. So improvement and verification for the core issue, but not yet resolved completely. My next (and hopefully final fix) is to move the O2 sensors into the header collectors, so upstream of the V band connections. I was hoping to not have to go there because it involves pulling the headers and welding new O2 bungs on will mess up the header coating, but having the engine perform at it's best is more important to me than the hassle and a bit of touch up on the headers.

 

[Marcus]

All interesting reading Joel... very many thanks... I will first try to seal up my collectors to stop any air getting in ... as always its an elimination process ... Good luck with your fix... Hopefully this thread will help other guys experiencing similar issues... I plan to post an update next week from the workshop ... cheers all.....

 

[Markus]

Hello Marcus,
Like always pictures help a lot - would you mind to post pictures of your collector / O2 sensor location (which is a topic of it's own...)
Regards,
Markus

 

[Brian]

I'll pile on with the O2.

I think that's one of those "self learning" EFIs, and ANY exhaust leak will give a lean signal to the ECU, making it pour on more fuel at that part of the fuel table. The simple little ECu doesn't have the good sense to know it's not lean, it's misfiring because it's pig rich. (ECU doesn't have eyes that burn from the unburned fuel)

 

[Marcus]

OK fellas picture attached of sensor in the collector... you can see there is some sign of exhaust leaking so selling this might help... I am also wondering if running the car now at non altitude (less thin air) in UK might have effected things so perhaps settings might need adjusting but will start by trying to seal collector....

 

[Chris Kouba]

Can you take it out of the self-tuning/learning mode? Or limit the amount it can play with the mixture?

 

[Markus]

The collector on the other side shows little to no signs off leakage (at least from what is seen on your pic) - you could put the O2 sensor there and see if things change to the better.....

 

[joe]

You need to check for an exhaust leak on the O2 sensor side. Reverse the hose on your Shop Vac (if you have one) so it is blowing air out of the hose. Shove it in your tail pipe and tape it up to seal. Use soapy water on the slip joints and check for bubbles. I had the same problem with the Holley Terminator X ecu and ProFlo MPFI system on my 66 Mustang.

 

[George]

I had the same problem and without a doubt the blackened part on your collector pipes is definitely an exhaust leak. I corrected the leak by taking it apart and using Permatex high heat gasket maker. Issue resolved. Clean out your connections and place a double bead on the inside of both collectors and let it sit overnight. Someone on this forum posted it and it worked for me. No more rough idling.

 

[Brian]

I would suggest this is not a permanent fix, but should hold long enough to let your ECU tune itself.

After it is tuned and running good, find out how to lock in the VE table (or whatever they call the fueling tables) and don't let it start screwing things up if or when the permatex burns out.

I have megasquirt on a Cobra. Once it's running, I turn off any ability for the ECU to correct based on O2 readings because it seems exhaust leaks always return. It may be the case you have to remove and unplug the o2 sensor and cap the port.

 

[Marcus]

Just an update all... So I was able to remove my O2 Sensor in the collector resealed the four headers, cleaned the Sensor with carb cleaner and compressed air and refitted same.
Engine now running far better and I plan to put some miles on her in what's left of the UK Summer...
Thanks so much to all that contributed to help me with the issue.... moral of the story make sure headers sealing correctly and clean Sensor...
Cheers All....