I've been bugging you guys about this too much, but this is driving me crazy.

I think I've addressed everything I should have to get rid of this missfire: upgraded ignition coil, vacuum lines, air filter, plugs, wires, cap, rotor, fuel line, fuel pump was recently changed. What else could this be?

Another point of consideration: I am running a cold air intake and an MBC. The missfire hits at 11 psi on my boost gauge and is more prominent when the engine is less than fully warmed up and the weather is cold (I try not to get into the throttle before than, but sometimes merging on the freeway requires a little extra throttle). Also it happens more when I get on the throttle and get an aggressive downshift.

It feels like I've lost some power at the top end, but that could be me getting acclimated and less impressed.

I got a check engine and it pulled a boost solenoid and missfire cylinder 1. This would suggest overboost, but could my gauge really be off by that much? Also the stock gauge is at or just over 3/4 of the way to the max when it happens.

I have an equus boost gauge maybe these things are just garbage and I am actually hitting 15 PSI?

 

pull out the mbc and run it at stock boost. see if you still have an issue.

 

Thanks Tony,
The missfire is gone while running stock boost, but the car is boring. I'd like to run more boost but want to make sure everything is working properly. So if I am getting a missfire at 12 PSI what would be the likely causes vs. my boost gauge sucks and I'm actually hitting the fuel cut which is causing the misfire.
I will probably get a re-mapped ECU in a couple months, I've just got to land this next promotion

 

The remapped ECU is takes away the fuel cut off. I love it. Have you replaced your ignitor? (I think thats what its called). Its the little black box that feeds voltage to the coil.

 

I have replaced the ignition coil with the MSD coil upgrade.

 

Something that plagued Honda Civics in the early years was the ignitor in the distributor. At higher RPMS it would not send the correct signal to the coil and cause a misfire. I dont think the Volvo has an ignitor in the distributor, I believe the pickup is on the flex plate. The component that recieves this signal and translates it to a spark pulse for the coil is that little black box that has the wires coming out of it for the coil. I dont know the name.

 

I have not changed that. If anyone knows the name and how to diagnose it that would be very helpful.

Thanks

 

What are your plugs gapped to? If they are gapped to .028, you could be getting spark blow out with the higher boost.

 

They are gapped stock. What should I set the gap to?

 

Final update. My gap was too big. I set it properly and the car runs spectacularly now. Thanks for the help!

 

I just had to google spectacularly to see if that was a real word. First time I've ever seen it in writing. Haha. It's also a funny word to say.

Glad to hear your car is running awesomely spectacularly though!

 

yeah, I'm kind of a dork . . . and by kind of I mean totally.

 

Excellent! what did you set the gap to?

 

I set the gap to .025. I searched and found that someone running a similar set up in terms of boost set their gap at that. It might have been Tech, in any case it was someone that knew what they were doing.