Honda start up ussues

[cjsmith]

I'm building up a FF with a Fit engine and can't get it to start. I'm using an engine and engine wiring harness that has been used on a different FF car that worked fine. I have a new chassis harness from Honda. The car will crank, if I put fuel in the throttle body it will start to run. The fuel injectors are not operating. I have wired the Fit master cut off switch per the instructions. I have 50 psig of fuel pressure going to the rail. I have checked all the ground connections and injector plugs as well as the other sensor plugs. Could I have a bad chassis wiring harness ? I can do basic wiring but this one has me scratching my head. Any help is appreciated.

[David Ferguson]

What is the voltage while cranking? I seem to remember the Honda ECU's would not try to run if the voltage was too low.

Try running a big external jumper battery, or run the starter off a different battery so the ECU doesn't see a voltage drop.

[PK]

I had that happen when I first tried to fire up my Honda conversion. My issue was that I had ignored the 'Z' wires in the loom. When I shorted them together, it fired right up.

[Messenger Racing]

?!#@

[cjsmith]

PK, I'm running the 2 purple "Z" wires trough the main shut off switch as shown in the manual. The 2 purple wires on the Z post on the load side and the ignition, yellow wire to the line side of the Z terminal. You are saying take them off and connect them together ?
Race Dog, yes I have an AIM system, I can see that some of the channels are reading, water temp, oil pressure and so on.

[problemchild]

PK, I'm running the 2 purple "Z" wires trough the main shut off switch as shown in the manual. The 2 purple wires on the Z post on the load side and the ignition, yellow wire to the line side of the Z terminal. You are saying take them off and connect them together ?

Phil was suggesting that if you do not have the correct Master switch, then you can temporarily connect those Z wires to get it going. If you have the proper switch (which you do), then turning the switch on, is doing the same thing.

Guys. I have been trying to guide Chris directly. Chris has another Honda car there to compare to, the correct master, and the HPD documentation. He has been racing a FIT powered car for many years. He needs to get out a multi-meter and do some troubleshooting.

[kdl]

if you have another ECU try swapping. I received a new from HPD ECU (first gen) which had a programming issue and was not reading supply voltage correctly, it was reading lower than actual. Enough so the car would not fire up, swapped out with another ECU and startup was immediate.

Keith

[cjsmith]

As a follow up, after checking connections and changing out components, the hardest thing to change that was the problem was the new chassis wiring harness. I could get power to everything but the injectors. Thanks to all that helped with advice. I'll be calling Honda tomorrow.

[Messenger Racing]

Congrats Chris,

Glad you solved it - you did the right thing - one step at a time. Stay in touch and good luck.

Jay

[Richard Hybels]

I thought Honda was done with us and turned it over to Fast Forward.
Is Honda standing behind the harness?


Hybels

As a follow up, after checking connections and changing out components, the hardest thing to change that was the problem was the new chassis wiring harness. I could get power to everything but the injectors. Thanks to all that helped with advice. I'll be calling Honda tomorrow.

[Messenger Racing]

Fast Forward is not involved in the electronics side of the discussion - Honda still is. There was some talk of freeing up the wiring harness manufacturer to sell direct but I have not heard any recent news on that front.

Quicksilver is also a great help on some of these issues but I believe full harnesses are still on the Honda side.

Jay

[hotarizona]

I have found from years of experience and research that usually the last thing you check is always the problem....... Glad you resolved the issue. I chased a wring issue on a fit motor for over a year. Th car would just shut down when idling in or through the paddock. Replaced a bunch of stuff and found out that I had a bad master switch...

School Of Curly, Moe and Larry

[Richard Hybels]

My car would idle about 40 seconds and quit. Like you I changed out the master and the problem has so far disappeared. I took the master apart but found nothing obvious.
I currently use a Bosch all metal master. (Best deal on Summitt Racing)
There is talk above talk about a “correct” master. I don’t imagine I have that so I guess the previous owner that did the Honda conversion figured something out.

I have found from years of experience and research that usually the last thing you check is always the problem....... Glad you resolved the issue. I chased a wring issue on a fit motor for over a year. Th car would just shut down when idling in or through the paddock. Replaced a bunch of stuff and found out that I had a bad master switch...

School Of Curly, Moe and Larry

[Lotus7]

My car would idle about 40 seconds and quit. Like you I changed out the master and the problem has so far disappeared. I took the master apart but found nothing obvious....

I'm sadly familiar with Honda harness issues, but curious how a master switch issue allowed the car to run for 40 seconds and then die? All I can see there is maybe a heat-build-up-until-failure scenario, which if so, doesn't sound like the master switch would be the primary culprit.

Anyone have insight?
thx

[DaveW]

I'm sadly familiar with Honda harness issues, but curious how a master switch issue allowed the car to run for 40 seconds and then die? All I can see there is maybe a heat-build-up-until-failure scenario, which if so, doesn't sound like the master switch would be the primary culprit.

Anyone have insight?
thx

A combination of light contact pressure and a slight amount of contamination at the contacts could cause heat & resistance to increase just enough to kill the engine - you might be able to see voltage to the ECU decrease on your engine data.

[hotarizona]

A combination of light contact pressure and a slight amount of contamination at the contacts could cause heat & resistance to increase just enough to kill the engine - you might be able to see voltage to the ECU decrease on your engine data.

Dave you hit it on the head. It had to be a build up of corrosion or a burnt contact area that would show resistance to the point that the engine would just shut off. We would cycle the master switch and then the car would magically start. We thought we were just cycling the ECU and it would reset and then work fine. We replaced the ECU with a new backup unit and the car fired right up so we buttoned it back up and rolled down to grid. Started the car again sat on grid for three minutes and the car just shut down. The crew member smacked the top of the master kill switch and the car immediately filed back up. Rolled out to the track and ran the entire race without issue. Was rolling back through the paddock and the car again just shut down. Contacted Pegasus and ordered a new master from them and never had an issues again. What I was told is that if you leave the master on for on for extended period of time that it will cause a hot spot on the contact and will end up doing the same thing all over again. I would suggest keeping a spare in your trailer just in case. It's a cheap fix and will keep you from spoiling your entire weekend. I spent many hours chasing an intermittent problem that could have been solved in a simple fifteen minute switch replacement. The problem was not the main terminals... it ended up being the two terminals under the switch that control the Z-Wires that send power to the coils.

Again its always the last thing you check Knuk Knuk Knuk

[DaveW]

I have found from years of experience and research that usually the last thing you check is always the problem....... Glad you resolved the issue. I chased a wiring issue on a fit motor for over a year. Th car would just shut down when idling in or through the paddock. Replaced a bunch of stuff and found out that I had a bad master switch...

School Of Curly, Moe and Larry