We got a code 34 over here!

[My_Q45]

Hey,

I just ran a self diag. on my 94 Q45 & it came up with a code 34. I currently have one of those cheap e-bay cd manual's that don't help that much, but it says the next step is to see if the harness is bad or the sensor. It has a little pic of the harness, but nothing to disguinsh it from the others. If some one can tell me how to id the harness & the test procedure that would be great. I have a volt meter, but I don't know which setting to put it on.. If it is the sensor(s) bad I guess I'll be taking off the pleum, but before I do that I wanted to test all the injectors so I don't have to do this twice. If some one can post a how to for testing the injectors & knock sensors that will be a GREAT help.

Thanks!

[90Q45blue]

I don't have my manual handy but when I get home I'll get back to you if someone doesn't post the answer first.

FYI, if it does turn out to be a knock sensor, it's best to replace the harness as well. You're already down under the plenum, it's only 40-50 bucks and it saves you a ton of work later.

Nick

[DAEDALUS]

http://home.socal.rr.com/robverna/injks.htm

This site comes and goes. Sorry guys, I only have 5MB to work with via my ISP. I'll maybe get a dedicated site soon. Bummer of an error, but there's a lot of good you can do for your car while you fix the knock sensors.

[My_Q45]

Thanks for the reply guy's!

Hey Daeduls I am actually starting up my own car site at car-nutz.com & would be glad to host the files for all the nico members! I've gotten a lot of help from every one & if I can help others I would!

If you want me to host the file, let me know! I can probably set up a site like nico.car-nutz.com or car-nutz.com/nico I don't know how many sub domains I am allowed.

[My_Q45]

OK,

I have a few stupid follow up questions after looking at the directions. 1)Do I probe them with the car off, ignitoin on or running?2)I guess I probe them disconnected?3)When I did it with the car off the rt sensor changed readings compared to ignition on. I don't know how to read a volt meter that well but on it read 10. while the left read just under 5 all the time. I guess I shold add 2 zero's after each number.

If someone can walk me throught it step by step that would be a great help

Thanks!

[DAEDALUS]

You want to measure resistance (ohms), which requires no voltage through the circuit. Disconnecting the battery from the car while working is always good practice. But it really shouldn't matter, since you're disconnecting the circuits from the ECU and power. Perhaps it isn't clear--make sure you're measuring the sensor-side harness, not the ECU side. There should be some annontation on the meter to tell you what the units are. Usually they come in multiples of 1E3, so 5 would probably mean either 5, 5,000 or 5,000,000 ohms.

Thanks for the hosting offer. Maxnix offered up some space earlier as well. But I should have lots of space as soon as my hosting request goes through.

[Q451990]

I forgot to mention... The Monarch said we could post them here on NICO. Maybe we could start a reference section here on the site?

Heath

[My_Q45]

OK

I tested the ks harness & got no reading which I assume means at least the harness is bad or disconnected. I assume the pleum has to come off to look at it closer. I also tested the fuel injector harness & my meter registered 0 on all injectors. My meter has 2 ohm settings x10 or x1k. I was using x10. Is this correct? What do I do now?

Thanks for the help!

[Highway Q45]

I forgot to mention... The Monarch said we could post them here on NICO. Maybe we could start a reference section here on the site?

Heath

I'm all for it. With all the typical Q repairs that come up it would be nice to have a "Garage" section where standard repairs and upgrades are detailed. Things like brakes, shocks, plenum, injectors, HVAC, trouble shooting come to mind. It would sure cut down on searches.

A reading of 0 ohms sounds fishy, the car wouldn't run with all injectors at zero.

[DAEDALUS]

Sounds like you need a more sensitive ohmmeter. Still, even with x10, you should have gotten 1.2 or thereabouts.

[Qgrappler]

Check to make sure you're reading ohms by touching the probes together=== the meter should read zero(which is usually full scale deflection)---if the needle doesnt go to exactly zero, use the adjustment to set it that way when you have the probes connected to each other. The ohms scale selector sometimes has the omega symbol to identify it.

If its a digital meter, it takes some time for the logic circuit to find the right reading. Touch the probes and they should still read zero after a moment or two.

Make sure you're making good contact on the contacts when you're measuring.

[My_Q45]

Thanks for the help!

I forgot about the calibration screw. I re-tested everything, but I still have no reading for the knock sensors. The fuel injectors came in from 6 of them at 18 1 at 26 1 at 40Is the correct number around 12? Isn't it odd that I would have 6 bad injectors that have the same number? Could my meter be incorrect? Has anyone had good/bad experiences with either remanufactured or sonic cleaning them?

Thanks

[DAEDALUS]

Nominal is 12 ohms, anything outside of 10-14 ohms is out of spec per the manual. I don't think the injectors can be remanufactured, just cleaned and maybe spray pattern measured. Neither of these will help a bad resistance reading. If you have an electronics store (Radio Shack) nearby, go buy a 12-ohm (or close) resistor for real cheap and figure out if your meter is bad or not. If both knock sensors are open circuit, I would suspect a bad harness connection. No way to be sure without pulling the plenum.

[sultan]

what happens when the ecu gets code 34? does it show a constant knock and retard timing, does it show no knock and do nothing, or does it depend on what caused the code, i.e. abnormally high or low voltage?

i ask because i'm showing a code 34, and it will probably be a couple weeks before i can replace the knock sensors and wiring harness. is it fine to just drive the car?

[PalmerWMD]

In summer thats real dangerous, as even with hi octane fuel you may get some knock, especially on higher mile engines (deposits).

I would minimize to only absolutely neccessaruy driving with the absolute highest octane you can find.

Fred..