Code 34 & 51?

Nissan 300ZX technical discussion forum: Maintenance, performance, installations, modifications, how-to's and troubleshooting.
redincali
Posts: 107
Joined: Mon Aug 04, 2008 4:07 pm
Car: 91 300ZX NA SLICKTOP

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Well, i thought i was done with my car yesterday after installing the heater. but last night when i started my car, the check engine light came on. so i just ran a diagnostics on it and got the codes 34 and 51. the det sensor and injector circuit. does that mean i have an individual injector bad? i just got the codes so im going to do some research but i thought i would start here first.


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evildky
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Car: 71 Datsun 240ZT
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a dead injector might explain the knock code

step 1 would be to ohm the injectors

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Ace2cool
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Car: 1991 Nissan 300ZX TT
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Yep, you got it. It's probably running rough. The knock sensor is being set off by the misfire on the dead cylinder. Ohm injectors to figure out which one it is, and replace it.

redincali
Posts: 107
Joined: Mon Aug 04, 2008 4:07 pm
Car: 91 300ZX NA SLICKTOP

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ok thanks. ill have to check it out this weekend. im assuming ill have to remove the upper plenum to get to them, or is there an easier way? should i not drive while its like that or is it ok as long as i take it easy. thanks again

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vape-one
Posts: 416
Joined: Wed Oct 29, 2008 6:01 pm
Car: 1990 300zx

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evildky
Posts: 14225
Joined: Sat Jan 31, 2004 9:23 pm
Car: 71 Datsun 240ZT
87 Nissan 300ZX N/A-T
06 Nissan 350Z GT
Toyota Tundra TRD RW
Location: Louisville, KY
Contact:

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you can ohm the injectors with the plenum on, the back ones can be tricky but you can do it

redincali
Posts: 107
Joined: Mon Aug 04, 2008 4:07 pm
Car: 91 300ZX NA SLICKTOP

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and a month later.... heh finally got time to put it back together a couple days ago. she started right up but im still getting a det. sensor code. is that normal? its the only one coming up after replacing my injectors. I actually had 3 that were way off on the ohms.

the car is still idling high, at about 1400rpms. eatin gas like crazy too. tomorrow ill check the timing, or this weekend. while i had it off, i decided to paint the plenum and valve covers. didn't want to over do it tho. but a few scratches did get created while putting everything back together. thanks for the help again, this forum is the best.

just in case u wanted to see

before...

after...

yes, i know. the last owner straight man handled the intake pipes and got crazy with a bright red and blue spray paint on the engine. the shroud is the next to be painted. along with intake new pipes and red couplers. dont want to 'rice' this car out, just want the engine to look better than it did. as for the outside, i want all stock except for my hood, nose panel, and hatch. which will be in carbon fiber.


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