Fuel injectors

[beachfan]

Hello,

1990 Q-45 Does anyone have a step by step guide or any pics of fuel injector replacement? Also, how about the same data for spark plug repalcement? I am having rough idle at 136k and am trying to trouble shoot. Dealer ran a poiwer balance test for 100 bucks and told me #5 and #8 injectors not working properly. Talked to another mechanic and he suggested it may be fouled plugs. I do not know the last time plugs were changed. I have obtained the NGK's from Scottsdale for replacement and figured I would try the plugs first as injectors run between 1300- 2000 for all 8. I have just added a can of 44k and a bottle of ISOheet since I have ethanol gas but I have only been through 1/3 of the tank with very limited improvement. Any othger suggestions on what to check before replacing inhectors? Thank you very much for your time.

[burijon]

Wooohooo Virginia! We should team up and do our plenum work together.

You can get the injectors brand new at Infiniti of Scottsdale for $170 a piece:http://www.infinitipartsusa.com

This will give you some good advice needed to remove the intake to get at your fuel injectors:http://www.q45.org/plenum.htmlhttp://fo ... ?id=212964

If you can afford it plan on doing everything under the plenum. The purists will tell you to do EVERYTHING as money is not an object for most people here and to avoid repeat labor. The practicals will tell you to do what you can afford. Depends on how much you love the gas guzzling beast.

I'm very close to attaining all my parts to achieve spiritual creaminess of Q45 wizardry of an official plenum remover!

Save yourself a boatload of cash and read everything NICO has to offer and do it yourself. Don't be depressed if it looks daunting you can learn and be better for it!

Welcome to NICO!

Get yourself a factory service manual from here:http://www.phatg20.net/modules...id=62It only starts at 1994 but has most of what you will encounter.

Good luck!

[Q451990]

I would ohm the injectors before you pull the plenum... There's always the possibility that the injectors are just physically clogged from debris and buildup. You may be able to save them with a pressurized rail flush...

Did the dealership give you the print-out from the power balance test? If so, please post the results.

Heath

[beachfan]

The dealer did not provide me with a printout, just a bill that said #5 and #8 were not performing correctly. Is that something they would keep ( had it done a couple of weeks ago)? Also asked them to perform a fuel rail flushg and they said not to do it as it could clog the injectors with old seal material that would be jarred loose by the flush.. I did not agree with that assesment but they are the only dealer in town. I called around to several other shops in the area and no one even knew what a fuel rail flush was. ANy recommendations on where to get it done? I am in central VA , Richmond area. I would even travel a little out of the local area if i could get a good recommdation for a shop. Thanks

[mxr662]

I would ohm the injectors before you pull the plenum...

Heath

Here is the link for how to ohm your injectors http://www.q45.org/ohminjectors.html

Read about your timing chain guides here: http://www.q45.org/ohminjectors.html

Welcome to NICO

[maxnix]

How about T3 in Atlanta or Keith Vanmeter in NJ?
Modified by maxnix at 7:32 AM 4/3/2007

[Ozzie]

Here is the link for how to ohm your injectors http://www.q45.org/ohminjectors.html

Read about your timing chain guides here: http://www.q45.org/ohminjectors.html

Welcome to NICO

whoopsie!!!

timing chain guides here: http://www.q45.org/guidereplacement.html

[Q45tech]

Prior use of BG44k in gasoline is helpful prior to a rail flush as the mild concentration of extra detergents PRECLEANS some of the injector screen filter varnish or at least puts it back in suspension in the larger quanity of gasoline.

Very important to change fuel filters frequently and after aggressive solvent cleans of system.

[Q45tech]

Prior use of BG44k in gasoline is helpful prior to a rail flush as the mild concentration of extra detergents PRECLEANS some of the injector screen filter varnish or at least puts it back in suspension in the larger quanity of gasoline.

Very important to change fuel filters frequently and after aggressive solvent cleans of system.

http://www.bgfindashop.com/locator/index.php

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