misfiring

[madseacow]

I just installed 550's and now I've got a major misfire, I've checked the injectors and they're in the right order, and plug wires are in order, what else could cause this?

 

[plaaya69]

Are the 550's new or used and also do you have a Lexus AFM?

 

[madseacow]

new lucas (the cheap ebay ones) I've never heard anything bad about them, ofcourse with my luck I'll get the one crap batch. I've got the maf, fp, fpr. I'll take a video of it tommorow.

 

[lagged]

how major is the misfire? is it as if an injector or spark plug wire is not connected?

you may have left a connection loose, either the coil packs, injectors, or plugs.

check everything you removed and double check your wiring.

 

[madseacow]

I found where I had swapped #5 & #6 (I think....) so I flipped 'em back and it's still misfiring. I'll recheck all my injector harness' (Ughhhh) The CPS couldn't just go out over night? cause I'm also getting code 12 for the first time. hopefully thing will have warmed up by tommorow and I can go have a lengthy look, but I'm just making sure there's not something I'm over looking.

 

[oscar35783]

new lucas (the cheap ebay ones) I've never heard anything bad about them, ofcourse with my luck I'll get the one crap batch. I've got the maf, fp, fpr. I'll take a video of it tommorow.

What other mods do you have?

 

[lagged]

usually if the car was running good before a repair/mod and then you have a problem after the repair/mod then that is most likely the source of the problem.

go over everything you touched and look for mistakes.

 

[madseacow]

check my injector wiring. it's an 88jdm:
#1 yellow & white/blue
#2 Black & white/red
#3 white & red
#4 Yellow & white/blue
#5 Black & white/red
#6 Red/white

 

[madseacow]

n/m I checked it, it's right.... maybe I've got a bad injector.

 

[Dirgle]

Read this.

Missing on a cylinder - a lesson learned

Strange things can happen, and is very possible that it is your injectors, but make sure you check everything. Even the small stuff.

 

[madseacow]

damn I got all excited and ran out to check my plugs (cuz that's exactly what it sounds like) nothing as far as I can tell. I'll put a new set in.... but my hopes are low. I've gone down the line disconnecting fuel injector and it only drops the idle, no misfiring. so it's gotta be spark related. I've got spark comming from each coild pack.... but the timing could be off? I've got a code 12... so should I buy a new CPS?

 

[jdub]

What is your fuel pressure, vac line attached?

 

[madseacow]

champion plugs are the problem, 2 plugs were broke... on a side note, my fuel pressure is set at 34-36 w/vac, havn't done 12v mod yet but I've got the relays and fuses waiting to go on.

 

[madseacow]

n/m still missfiring, this time it started out good, then 2 seconds later it starts acting up. ignitor or cps?

 

[jdub]

Stock fuel pressure is 23-30 psi w/ the vac line attached...my Lex/550 combo seems to like 27 psi.

Check your spark plug wires...might be time for a new set.

 

[lagged]

at this point you should be following the troubleshooting procedures in the TSRM.