running rough after new injector install *solved*

[eyezpinned]

had 2 leaky injectors, so i decided to change them (straight oem not an upgrade). now after the install car is running rough at lower rpms (sounds like a lawnmower) was thinking maybe air got in the system. for the record ive only ran the car 5 miles since the install, so maybe it'll work itself out? anything else i should look at?

[davmac]

It sounds like one or more injectors are not working so your running without 1 or more cylinders firing. The roughness is masked at higher rpms.
I assume the car was running better before the injectors. If true then the new injectors or if you disturbed others to install may not be sealing. Review your install. Check all your injectors are working - usually a resistance check with ohm meter with the car off and a stethoscope listen with the car running to confirm. Use new o-rings on all that you had to remove. Make sure everything is tight. Good luck.

[SuperK]

This exact thing happened with my injectors.

Go ahead and run some injector cleaner, who knows how long those injectors have been sitting, the fuel may have started varnishing.

It'll help, but I guarantee you it won't solve the problem.

Send your old injectors in to get cleaned professionally, and if they don't rebuild the injectors, make sure to get an injector rebuild kit as well.

But first steps first, get some injector cleaner and run a generous amount though it.

[eyezpinned]

the injectors are BRAND NEW, not used, not rebuilds

[SuperK]

do it anyway!

[SuperK]

haha, if you had some bad injectors, it might have fouled out a couple plugs. Did you try purchasing a set of ngk coppers and doing a tuneup?

[Mooneggs]

yeah like superkid said you should check plugs/wires replace as necessary...

[davmac]

haha, if you had some bad injectors, it might have fouled out a couple plugs. Did you try purchasing a set of ngk coppers and doing a tuneup?

Great point. If all the injectors check out as good and the install looks OK then plugs / wires could be causing the misfire.

[eyezpinned]

okay long day.... so i get up this morning & me and my buddy go to work. as we checked the injectors, we find that unclipping one particular injector had no affect on engine performance like the others did. ding! ding! ding! dead injector. so i had to throw one of my old ones back on until i receive the replacement from rockauto (should be here by friday). so i take her out on the road with the three new injectors & the best of the old ones, and she runs like a dream: strong steady acceleration, very quiet idle, really nice response... BUT i start smelling gas... the old injectors are about a mm shorter then the new ones, so the old one didnt re-seal. so i was up at school in ice-rain, gas running out of a badly seated injector, ready to trade my soul for a 12mm socket. basically i had to unhook the one injector until i could get it home and redo the rail. so i redid the rail, let the car run for a half our and then took it for a drive and shes bone dry. amazed at the difference the 3 new injectors are making, looking forward to installing the replacement. ill update w/ an mpg report. thanks for your insight guys.