alane

so i replaced a bad injector, and now my misfire appears to be gone. I can rev it up and it no longer vibrates, or shakes, the exhaust sounds smooth now, not spuddery. BUT

but now the car idles too low, and i cant seem to fix it. adjusting the idle screw did do much. i quadruple checked all the vacuum hoses, and they appear fine...anyone have any ideas???

ăndrew

90GXE->SE

I am having the same problem i replaced all my injectors with used ones which regained all my lost power but will not idle checked over everyting 2's found nothin talked to some of my buddies over at the nissan dealer in the service dept. they told me to check the resistance on the injector and check the connection from injector too injector connector havnt got time to do this yet but when i do i well let ya know what is going on

alane

thanks, my problem still persists, its pretty bad, it wil sumtimes die when it is trying to idle.

Nismo87SE

The nissan service manual shows that you have to put the ECU in diagnostic mode III then race the engine 2-3 times under no-load conditions then allow it to idle for about a minute. This will lock in base timing and idle so you can adjust it.

doomtoo

I got help from someone else off here. Does your car take a while to start when you're turning the key? Mine was like wrrr-wrrr-wrrr-wrrr-wrr.....wrrr-wrrr-wrrr-wrrrrr-r-rrroooom!
2 of the O-rings were damaged when my friend put them in.
SOB also fropped crap in my engine! They pulled out a washer, but there's still something else knocking around in there...

90GXE->SE

Ya I think thats what might be the problem is the o-ring cuz on the back to left and middle injectors i can see a leak coming from around where they are suposu seal just some wetness but that might be enough to loose pressure at low rpms. Now to put it in diagnostics mode i have to turn the idle screw all the way counter clockwise correct then race the engine 2 or 3 times then i can use that screw to adjust the idle speed.?

90GXE->SE

Problem Solved it was my upper intake plenum gasket , ended up making my own with gasket material uz f'in autozone wanted $64.00 for gasket which was a rediclious price so i bought a role of gasket material and kut it myself anyway that worked wonders idle is back to %100 and since i thought it was injectors i bought new 300ZX injectors and fuel pump and vortec FMU. The gains are like WOW smoked a 1997 Monte Carlo Z34 never could taken it before injector upgrade any way im on my way to a turbo upgrade ill post pics soon as i start fitting my garret T3.

Tom

That's amazing that Autozone wanted $64.00, because I only paid $8.41 for that gasket at the Nissan dealer last year.

broncoguy

I bought the gasket at Autozone for about $48.00. It's not just one gasket, it's actually 3. The upper and lower plenum gasket, as well as 2 metal gaskets with rubber inserts. I think they must go below the lower plenum, but you don't have to take that off to change the injectors. In other words, I think it is a full intake kit....but still pricey at $48.00. Dealer didn't have what I wanted in stock, so...

alane

what about gasket maker, the black rubber stuff? would that work too you think? or should i buy a new gasket?

90GXE->SE

They make the actuall rolls of gasket material atlest they have them at my autozone in Buffalo NY its in a package its 12" wide and 4 feet long i had to make 2 different pieces but at the seam just smear alittle extra rtv gunk.

alane

do the old gaskets really need to be replaced? or should i just add RTV to the old ones to reseal them?

90GXE->SE

Prolly ur call what kind of condition are they in mine were shot half was on the upper plenum and the rest stuck to the lower. I would say if its at all broken then replace if its still all in one piece then u could try the RTV genersouly on the old one