Adrenaline XXIV

I'm trying to learn as much about Hondas as possible, but I'm not exactly knowledgeable besides what I learn from HT and personal experiences, so please bare with me.

When driving my car at a steady RPM it begins to break up and crackle. It doesn't backfire but it does feel like I have no bottom end power. Knowing that it could be so many different things, I started performing a trial and error. So far I have bought a brand new cap and rotor, distributor, NGK plugs (my old ones were white upon removal), and a fuel filter. Still having the same problems. I know the firing order is 1-3-4-2 for a d16, but when I remove plug 3 and 2, it does not change the idle at all. The plug wires are sparking. The car definitely does not feel like it's running on two cylinders though. I have DSM 450CC injectors, I disconnected 3 and 2 for them, and the engine knocks, so those are fine. A friend of mine suggested that the timing could be off by just a tooth, but I've read that a single cam off timing will run like ****, way worse than what mine is doing. I don't know if it's a fuel rail or compression issue, possibly?

Edit: Modifications done to the vehicle that could cause fuel/ignition problems.

1993 Honda Civic Si
-t3/t4 57 trim turbo
-chipped p28 ecu tuned on 10 psi with Crome.
-DSM 450CC Injectors
-3" downpipe with full 3" exhaust, no o2 sensors.. turned off via Crome.

Any suggestions at all HT?

Nick

grumblemarc

iTrader: (4)

Why are you running 450's instead of the stock ones?

Adrenaline XXIV

Oh, I should have mentioned that. I'm running a t3/t4 57 trim turbo set up.

grumblemarc

iTrader: (4)

What are you using for engine management? The first thing I would suspect is an issue with the tune. But then pulling injectors and getting no change is an issue as well. Is this recently boosted? Did you perform a compression test before it was boosted?

Adrenaline XXIV

No, It's been boosted for about four months now and I just started having this issue a few days ago. It's a Crome base map that's proven. The engine did begin to detonate without an injector in, so they seemed to be working pretty good. Yeah it was tested before and was fine. Thanks for any feedback!

grumblemarc

iTrader: (4)

Never run on a basemap. I don't care how proven it is. A basemap is only used for getting you to a tuner. Each vehicle is different and needs to be tuned accordingly. Yes you can run on one but it's not recommended. Check in the Forced Induction forum and anyone worth his salt will tell you the same.

What were the compression numbers? Are you running an upgraded fuel pump?

Adrenaline XXIV

Ahh I don't remember what they were off the top of my head. I have a stock fuel pump, I was considering changing it to a Walbro 255 or another stock one as the car has 190k miles on the body so I don't know if it's ever been replaced. I was under the impression however that if a fuel pump is bad, you won't get any fuel at all?

grumblemarc

iTrader: (4)

Not true. The stock pump will not be able to keep up with the increased demand that a boosted setup with larger injectors puts on it and yours may only now be showing signs of failure. If you upgrade the injectors then it only makes sense you upgrade the pump. Hope no one told you that it would be alright to do so.

Adrenaline XXIV

Okay, I will get a Walbro 255 then asap and see if it fixes the problem.

Could this explain my horrible gas mileage? I swear I'm getting under 20 miles a gallon.

grumblemarc

iTrader: (4)

The poor gas mileage is probably the fault of the basemap you are running since the map on it has not been optimized. That's why you do not run on basemaps.