Injector lifespan? replace or rebuild?

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

1973Guppie

1973Guppie

10 Year 15 Year 20 Year
Joined
Jan 31, 2003
Threads
954
Messages
10,243
Location
"the whale's vagina", CA
Hi all. Working on getting my 80 trail truck up and running after it sitting for about 4 years. I have confirmed I have a bad injector on cylinder 5. Pulled them all and here are my readings in ohms: 5 (bad), 13.5, 13.2, 15.6, 13.1, 13.1

Factory spec is 13.4 - 14.2 so technically all 6 are out of spec. I had these rebuild about 50k miles ago when I did my head gasket. 1996 80 series 230k miles. I am happy it is just a bad injector and not an engine problem but new denso injectors are $$$$. I am trying to decide if I should have the 5 injectors cleaned / rebuilt or I should just bit the $$ bullet and buy new denso units?

Opinions / personal experiences welcome.

Thank You!

Noah
 
Set of new Denso 2-hole injectors (23209-74080)
Or, a set of new Denso 4-hole injectors found on the later 1FZFE with distributorless electronic ignition (23209-66010)
Or, pick up a set of known good used original injectors and send them out for testing/cleaning??

If you plan on keeping the vehicle/engine a long time, pop for the new injectors while they're still available??
 
When you say rebuild? What did they do? The denso injectors have nothing to rebuild, they just clean them and flow test them.
 
Before you decide they are out of spec, measuring low resistance is not easy with a run of the mill multimeter.

1. I assume you have a decent meter, not a HF $3 unit
2. You need to factor the lead resistance of your test leads (unless you have a fancy 4 wire set of leads and a meter than can use them...)
3. The tips of the test leads need to be in great condition.
4. Short the lead tips together and see what resistance is displayed, especially as you flex the leads and move the tips around against each other.

You can easily add 0.5 to 1 ohm with bad measurement technique and poor leads etc.

Anything other than cleaning and replacing grommets, there's no "rebuilding" going on. The failures I've seen and seen posted are usually the coil inside the injector (it's basically a solenoid) going bad - either open circuit or shorted turns when the enamel insulation breaks down.

cheers,
george.
 
Last edited:
george_tlc said:
Before you decide they are out of spec, measuring low resistance is not easy with a run of the mill multimeter.

1. I assume you have a decent meter, not a HF $3 unit
2. You need to factor the lead resistance of your test leads (unless you have a fancy 4 wire set of leads and a meter than can use them...)
3. The tips of the test leads need to be in great condition.
4. Short the lead tips together and see what resistance is displayed, especially as you flex the leads and move the tips around against each other.

You can easily add 0.5 to 1 ohm with bad measurement technique and poor leads etc.

Anything other than cleaning and replacing grommets, there's no "rebuilding" going on. The failures I've seen and seen posted are usually the coil inside the injector (it's basically a solenoid) going bad - either open circuit or shorted turns when the enamel insulation breaks down.

cheers,
george.
Click to expand...
yeah I figured there was a margin of error, quality meter, I am just wondering what the lifespan of these is supposed to be and if Toyota states after x miles they should be replaced rather than cleaned again, but it sounds like they are basically a forever item until they are not, lol.

I am gonna just get them cleaned. I may buy new ones someday if I rebuild the engine.
 
1973Guppie said:
yeah I figured there was a margin of error, quality meter, I am just wondering what the lifespan of these is supposed to be and if Toyota states after x miles they should be replaced rather than cleaned again, but it sounds like they are basically a forever item until they are not, lol.

I am gonna just get them cleaned. I may buy new ones someday if I rebuild the engine.
Click to expand...

When I did the HG on mine and had the injectors out I replaced the little filter baskets in each and cleaned using Carb cleaner & 9v battery to cycle each injector
Its pretty easy to do and theyve been perfectly fine.

the kit I bought with the filter baskets came with new rubber orings for each injector as well and was only about $30 AUD

 
I sent my dead one to rockauto as a 'core' and bought a 'reconditioned' unit for not many $ (a decade or so ago). Figured I'd have a spare that way.

cheers,
george.
 
You must log in or register to reply here.

Share this page

Back
Top Bottom