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Injector Swap and CA SMOG Inspections

splitkooks

shredder
NAXJA Member
I've searched high and low, with no real definitive answers, but are there any injector upgrades (Volvo or Neon or otherwise) that will pass SMOG?

Definitely not going to swap my injectors before my test, but wanted to try to pin down if anyone has had experience passing an inspection AFTER an injector upgrade or change.

Thanks y'all

P.s. 1990 xj
 
Never seen them check injectors. Can’t see how that would impact smog.
 
IMO, there are no significant injector upgrades for a stock or near-stock engine.
Those that experience noticeable positive changes with different injectors most likely had, old dirty injectors, to begin with. Sorry, no magic here.

The Factory injectors are large enough to compensate for minor upgrades such as headers or exhaust changes. A set of high quality, rebuilt and flow matched injectors is what you need.
My 1997 XJ has a full Banks exhaust, ported head and larger throttle body, yet it runs fine on the 22-year-old stock injectors. Good power and economy, with no indications of running lean.

BTW, my 2001 XJ has run a built stoker in California for a couple of years and it has passed smog twice. As long as it runs clean and LOOKS stock, you shouldn't have problems. The inspectors do not have x-ray eyes, internal parts are invisible, including the injectors.
I failed once due to a non-stock air intake tube, between the air cleaner and throttle body. Make sure your XJ has the stock air filter box and hose before going in for the testing.
 
I swapped to the 4 hole injectors years ago on my 2000, did provide a little better throttle response. It did not impact my CA smog at all.
 
I know several guys who run stroked 4.7's with 25lbs mustang injectors and pass smog. Just changing from a single to 4 hole injector is not going to affect smog.

I also agree with Lazyxj and have done the 4 hole injector mod. There is little to no difference (little difference from new vs old), it's more hype than actual upgrade.
 
I have 5.0 injectors and a fake clamp on cat ( just the metal outside, like a empty clam shell) I have passed smog in Oregon every time.
 
what is the part # for a set the 4 hole neon injectors that have the same flow rate as the stock jeep

I don't know what the reference vehicle is but I bought 0 280 156 007 Bosch's and they are great for a factory XJ.
 
I should add that year makes a difference, mine's a 2k.
 
I have 5.0 injectors and a fake clamp on cat ( just the metal outside, like a empty clam shell) I have passed smog in Oregon every time.

What year is your xj and where do you live? Oregon is interesting as if it's obd2 they only plug a scanner in, if it's under a certain gvw, no tailpipe test. If it's pre obd2 it would instantly fail without a functional cat as they do test tailpipe. Without a cat every car, no matter how well/clean it ran, would fail.
 
What year is your xj and where do you live? Oregon is interesting as if it's obd2 they only plug a scanner in, if it's under a certain gvw, no tailpipe test. If it's pre obd2 it would instantly fail without a functional cat as they do test tailpipe. Without a cat every car, no matter how well/clean it ran, would fail.

Does Oregon actually still do tailpipe testing on the pre-OBD2? NJ dropped that about 5 or so years ago...
 
Only inspection here in Kansas is to make sure the Vin matches the title number if you bought it out of state. Thats it. Ever. But I have always wondered something; I plan on putting a Bridgeported 13b in my 66 spitfire, if i was driving it, no cats etc, in California (not that i ever would) would they throw a fit or since its tagged in kansas could they do anything?
 
A vehicle that old does not require smog or any inspection.

And to the OP, I upgraded to 4 hole injectors in my 90 and never had an issues with visual inspection or actual smog output. The visual is only to look for modifications to anything smog related like the EGR, vacuum lines, CCV lines etc.
 
I have 4 hole injectors and passed smog test with them , They do not check the injectors and if you get the right ones they will flow the same fuel as the oem ones .In Ca. any thing 2000 or newer they just plug in to the computer and make sure it has passed all the self test and that there are no codes .
 
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