Injector help!

[dwhacks]

I noticed my duty cycle was up above 80% (it was 90% in places) so I looked into getting bigger injectors. It seemed like the DSM 450cc injectors would be big enough for my goals and can be had for a reasonable price. They also seem plug and play as far as installing and connecting them.

I am tuning with crome, on a gold rom.

I installed my new injectors and the car sputters and sounds as if its miss firing. If I try to rev it, it just keeps misfiring. I adjusted the offset to get it to idle using the same map I was using with stock injectors and by selecting the DSM injector in the list.

Any idea what is going on here? Anything obvious I can check? The injectors all checked out at just over 3ohms and I got them from what I think is a reputable seller on eBay (lancerevoiv).

I have tried a non gold p72 rom and it does the same thing.

Could this be an electrical issue? Is there something obvious I missed?

[GhostAccord]

What are your AFRs now that you have changed your flow rate?

How much did you change the offset? Did you use the fuel multiplier as well?

"Offset should be gradually increased in increments of 10.00 until the idle remains steady at 14.7:1 AFR and surging ceases. This is strictly trial and error; see Injector Battery Offset before adjusting the fuel offset." - http://www.ej9.ru/data/book/crome-v1...pro-dealer.pdf


Another great start up guide for Crome Pro.
http://www.xenocron.com/install/CromeGuide.htm

Half way down the page there is a section on adding fuel tools, his example is using 450cc injectors.

I don't remember where all this is in the Gold base, I'm sure it is in the list of options though. Been a while since I tuned using Crome.

[dwhacks]

Thanks for the reply, I've read both of those in my search and they don't really pertain to Gold it seems. Either way, I've followed them the best I could.

In Gold, under Fuel Corrections you have "General" and "Advanced". In general there's a drop-down to select the injector and then a box to type in Offset (Microseconds) and the relative option in Advanced is "Battery Offset (in microseconds)" which changes automatically when you change the injectors.

With just selecting the correct injectors my multiplier changes to 0.53 and I am able to start the car but it runs super lean (>19:1). Adding 970 to the offset under general gets me to ~14-15:1 but the car sounds like a hemi/subaru. If I try to drive it has no power and sputters along.

So I don't really think it's crome related, but I don't really know. I have tried different FPR (stock and adjustable) and I have moved the injectors around. All seems to have no change.

Any ideas?

[GhostAccord]

Check all 4 cylinders for fuel, spark and compression. If it sounds like a Subaru, you might not be firing on all 4 cylinders.

Also check to make sure that there are no inadvertent changes to the individual cylinder trims, fuel or ignition.

[93redcb7]

you need to check your original map to see if it actually had the stock size injectors selected, as when i did my tuning on mine i didnt even think to check that and ended up getting bigged injectors and i had to completely re-tune it because of that. if it was running fine with the other injectors, and the only thing that changed is those and the tune 99% sure it can only be one of those 2 things to be wrong with it

[Jarrett]

If I remember correctly, there were modifications required to trim the lower seal in order for the injector to seat properly. When you installed them, did they seats tightly and securely enough that you know you don't have a vacuum leak in the bosses? Is it possible that you have a vacuum leak somewhere else near the manifold caused when you were removing stuff to replace the injectors?


Something to check, anyway.

[dwhacks]

For the injector seal I used two rubber ones instead of one plastic and one rubber. I've read peoples using just one rubber seal and no plastic or boring out the plastic. Either way, I checked that by spraying carb cleaner on the seals and I hear no change in RPM so I don't thinking its a vacuum leak.

As for new injectors VS old, that is a good point. My old ones in gold seem to say
"Honda Civic 12ohm" and that's definitely wrong. I can see how that maybe makes me need the large offset, but I dunno about the sputtering.

I definitely have spark and compression on all 4 cylinders, but how can I check for fuel?

The funny thing is, when I first wired up the IAB I used the 12v from the ECU and I had this same sputtering. By grabbing 12v from the fuse box instead it solved the strange running. I'm wondering if some how its electrical.

I will check it out again after work.

I will probably try rebuilding my map and see what happens there.

[dwhacks]

Ok, possible false alarm! Not cromes fault, one of the injectors seems bad! I swear it checked out with the multimeter but I guess not. It was the one injector that didnt pass the "ear" test either (put a screwdriver on the injector and your ear at the other end and listen for clicking). I tested them with a 9v battery to see if I could hear them click open and one clearly does not.

I contacted the seller and he's sending me a new one, Fiewf! I hope that's all it was!

[dwhacks]

Ok all is well, I got my new injectors in, they all work this time and the car runs great! Seems even better then before actually. I went for a little drive with data logging and have to modify my maps a bit, but instead of making them all choppy they actually smoothed out! Much better!