Does This Add up?

[BLACKonBLACK98]

I bought a 90 w/113k miles on it on Saturday. Cleaned it up a bit and started adressing some minor issues. Well, everything was going so well that I started thinking about doing my injectors myself. I have never done injectors before but am comfortable with the idea (I am a car guy in passion and business, just not on the mechanic side). So I ohm tested the injectors.... now here's the scenario:

1) Car idles extremely rough with very little power when driving.

2) Checked ECU for codes on Sunday. Got a 55 (System OK)

3) Ohm tested the ks/injectors; 4 injectors and both ks dead, other 4 injectors 20 ohms +.

Now, to me it seems that with all those things wrong some kind of code should be thrown. What do you guys think?

[maxnix]

OBD I is dumb.

You should be reading the posts on under plenum jobs as you will be going to the very bottom for the KS, so consider VC gaskets, all hoses, IAC and EGR vavles, TB, plenum cleaning, plugs, and of course you have replaced your timing chain guides.

[Q45tech]

Be sure to check accuracy of VOM as a weak internal battery can create errors especially in low resistance measurements!!!!!

When you deal with 1,000 different early Q, you can almost just touch the hood with your hand and known which of the dozen or so COMMON failures you have.

Every 90-96 Q ever made needs new KS and harness the question is: is it at 9 years or 11.

[OnTheRoadAgain]

what are the symptoms of knock sensors?

the plenum removal does not overlap with valve cover gaskets, does it?

[snobrder]

I bought a 90 w/113k miles on it on Saturday. Cleaned it up a bit and started adressing some minor issues. Well, everything was going so well that I started thinking about doing my injectors myself. I have never done injectors before but am comfortable with the idea (I am a car guy in passion and business, just not on the mechanic side). So I ohm tested the injectors.... now here's the scenario:

1) Car idles extremely rough with very little power when driving.

2) Checked ECU for codes on Sunday. Got a 55 (System OK)

3) Ohm tested the ks/injectors; 4 injectors and both ks dead, other 4 injectors 20 ohms +.

Now, to me it seems that with all those things wrong some kind of code should be thrown. What do you guys think?

Hey man make sure and check that your pulling the codes right. I have the same exact problem you are having.

[BLACKonBLACK98]

OBD I is dumb.

You should be reading the posts on under plenum jobs as you will be going to the very bottom for the KS, so consider VC gaskets, all hoses, IAC and EGR vavles, TB, plenum cleaning, plugs, and of course you have replaced your timing chain guides.

i am using the q45.org instructions as a reference.

i did not see valve cover gaskets required but my understanding is theyare rtv which i have.

i puchased the ultimate kit from scottsdale so all hoses and ks/harness should be taken care of.

i saw instructions to clean the iac, but nothing about the egr (although i'm sure it can be cleaned as well). i negleted the pcv valve.

timing chain guides will have to wait, but this car will pretty much be sitting until next year.

[BLACKonBLACK98]

Be sure to check accuracy of VOM as a weak internal battery can create errors especially in low resistance measurements!!!!!

When you deal with 1,000 different early Q, you can almost just touch the hood with your hand and known which of the dozen or so COMMON failures you have.

Every 90-96 Q ever made needs new KS and harness the question is: is it at 9 years or 11.

dmm is a new fluke and i have been using it to test resistors all week. should be good.

ks/harness: check

[BLACKonBLACK98]

Hey man make sure and check that your pulling the codes right. I have the same exact problem you are having.

i'm pretty positive i did it right. its something i have done before (never on a q), and the fact that i got a 55 code leads me to believe i was successful.

i'm going to chalkit up to OBD-DUMB.

[BLACKonBLACK98]

thanks for the help guys. i have to say i am getting a little nervous now that i spent a good amount of cash. i' probably wont get to it until weekend after next so i'll be doing as much research as i can stand until then.

[maxnix]

timing chain guides will have to wait, but this car will pretty much be sitting until next year.

Good. Do it all at once. Not as easy if the engine is out of the car, but easier than redoing it with all the stuff in the way. Everything will have to be gone through anyway.

[goody90q45]

I'm pretty positive i did it right. its something i have done before (never on a q), and the fact that i got a 55 code leads me to believe i was successful.

The directions in the FSM can be confusing so try this:

(definition- Cycle: Rotate ECU screw fully CW, count to 3, rotate screw CCW)

With the ignition in the ON position the ECU should have a solid red light.>> After the 1st cycle the red light should flash. Read the codes.>> After the 2nd cycle the red light will be solid.>> After the 3rd cycle (no driving) the light should flash code 55>> After the 4th cycle the red light will be solid.and so on, and so on, and ......

When you're done reading codes make sure the screw is in the full CCW position and the light is solid. With 4 dead injectors you should be getting ECU codes. Is the CEL on? Start with a solid red light on the ECU, drive around for a few, and try it again. Good luck.

[Dabizzo1]

I got the code 55 as 1 of 2 codes when I first started fixing my Q over a year ago...obd1 is dumb indeed...2 dead knock sensors and 3 of 8 injectors dead with the remaining 5 originals on their way out. Dismantle the WHOLE plenum and EGR assembly and clean clean clean. Replace all vac lines that are dry rotted and if you are replacing more than 2 injectors at once, pull the rail so you do not hydrolock your motor. Before any disassembly, assuming injector replacement is a definite to do, depressurize the fuel system by opening the gas cap, pulling the fuel pump fuse and turning over the motor until it first dies, and then turning it over 2 to 3 times more. The 90 degree bend in the plenum from the egr will blow your mind...expect complete blockage of carbon, so use allen wrenches and pick tools to scrape it off. Even if you replace all 8 injectors with brand new oem injectors, a dirty plenum will rob the car of power...listen to the guys on this forum...A knucklebusting but spotless intake and 8 new injectors later, my near perfect running Q is a testament to their advice. Boris