Please help me.. I am finishing my '90 GTZ engine swap...

[tvc3-gtz]

Year: 1990
Make/Model: Cheverolet Beretta
Engine: Quad Four 2.3L DOHC
Trim: GTZ
Transmission: 5-speed
Mileage: (chassis + tranny) 118,000 + (replacement engine) 105,000


I need help. I cannot find where two of the plugs go to. I do not want to try to start it without everything being in place. Please check the pictures below I will highlight the parts I am having trouble with. If you see anything else out of the ordinary, please let me know.

I understand i still have to bolt the exhaust on and stuff, but I wanted to make sure everything was plugged in first. My ex-best friend at the shop really hack jobbed it. He didn't even put all the transmission bolts back in. Pain in the ass I ended up doing it myself, even though I had done stuff for him and he was supposed to do a good job on this car in return.

Anyways.. the plugs.. I hope I didn't miss something that will require me to take anything apart again. I just want this finished so I can register it and drive it.

[tvc3-gtz]

here are the other pics:

[tvc3-gtz]

and the rest of them:

[DOHC_tuner]

That purple wire goes to your oxygen sensor. Nevermind i just noticed the picture...its obviosuly coming from the sensor off the manifold. Just find a connector near the or around the driver side of the engine that will connect to that.

[tvc3-gtz]

i checked everywhere. i cannot find where this plugs into.. im getting annoyed.

[heavywoody]

The yellow/purple wire looks like the wire used to go from the crank position sensor to the coils. Granted my knowledge is based off V6's but I imagine you'd have to have that for spark on the Quads too.

[tvc3-gtz]

Thanks! I ended up somehow by a miracle reaching below the intake manifold and getting that plug for the crank sensor to coil into place and snapped it in nicely. Now I am still trying to figure out where the bloody H the exhaust o2 sensor purple wire end goes to. I know where the sensor is, its right on the exhaust manifold, but where the blazes does it plug into on the engine. I have searched high and low but cannot find the plug for it... I'm frusterated as hell because I have a Haynes, Chiltons, and official 1990 chevy beretta service manual and NONE of them are telling me. Either I am a complete idiot, or I am missing something because I cannot seem to find this anywhere...

Also, a new plug thats missing a home (see pics below). I believe the plus are Green + Green/White

[tvc3-gtz]

im about to give up... i cannot find the f****** o2 sensor pigtail i have looked everywhere over over and over again.. without a pic im screwed. can i just run the damn thing without the 02 sensor?

[woody90gtz]

That hardline looks like the vent for the trans. There should be one on the trans too near the top that gets connected to that one with a rubber hose.

That last 2-wire looks like an alternator hookup to me, or possibly AC compressor. Are either in that general area?

That o2 pigtail has to be somewhere. Is that o2 the original for the car and are you sure it came with a 1-wire stock? I know my 91 v6 came with a 1-wire and my 95 came with a heated 4-wire. Just throwing that out there. It will probably run without the o2.

[#1berettaman1991gtz]

the plug by the by the heater hose in your hand goes to a coolant sensor on the thermostat housing or near it on the cylinder head.
o2 sensor plug is black with a black or a purple wire.

[#1berettaman1991gtz]

the second photo looks like your missing the powers steering bracket that bolt to the 2 holes on the transmission and the brake booster tube bolts to the bracket.

[ifixalot]

In answer to,your question, the engine will run without the oxygen sensor but it will trigger the SES light.
The oxygen sensor is used by the computer to fine tune the fuel mixture. Without input, the ECM will estimate
the mixture with info from other sensors.
Unless the wire is broken off at the wiring bundle loom, I don't understand why you can't find it.
They make the connectors so one will not plug into another unless they match. The one for the oxygen sensor fits inside that one in the picture.
Wrap your hand around the wiring loom and "feel" your way down for a wire and connector hanging out of the loom. Try both sides of the car, driver and passenger. I have a 96 so your car is probably different.
The loom is covered by a split plastic corrugated tube. Maybe the connector got pushed inside the split of the tube.
It's gotta be there somewhere.

[Rettax3]

The pigtail for the O2 sensor SHOULD exit the loom near the ICM plug on the driver's side by the cylinder head. X2 on the 'new' two-wire plug going to the coolant temp plug -that is kind of a unique one for the Quad family. Yes, a one-wire O2 is stock for a Quad (and later 2.4 Twin Cams too, even the OBD2 cars use a one-wire in the manifold and a heated O2 post-cat). Since the connector is so slim, check to make sure it didn't get pulled back into the loom somehow. The connector may have been broken off too, if it was such a hack-job before you took over... Good luck.

[tvc3-gtz]

I ended up wiring it up, and thanks to all who helped, now just a few tinerkings and its ready for inspection/