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Multiple probs on motor install

512 Views 7 Replies 4 Participants Last post by  DJ420A
I bought this 90 for my wife cuz she really likes mine. Problem was it had a bad motor. So I bought a motor and tranny, cuz she wanted a 5 speed swap. I got everything in and running, pretty well.
Today I got it up to running temp and here are the probs I ran into,

1. Fluctuating idle, about 200-500 rpms
2. Running hella rich
3. Motor stalled on me, I tried to crank it over for a little and it wouldnt start. Now the starter wont turn over, doesnt even sound like its getting voltage, I just hear a relay.

Now my thoughts on the fluctuation and richness, is the O2 sensor, but Im not sure because Im used to 4 wire O2's and this has one, I dont if that makes a difference.
I messed with the TPS sensors adjustment and it seemed to smooth out the idle, but theres still a fluctuation and Im still really rich.
I ran out of time tonite so I didnt get to start testing stuff. Im stuck in the house with the kiddo tomorrow, so Im not going to be able to get on it till Tues. Thats why I figured Id ask you guys, so I can get a better idea on what to start on the next time I can get to the shop.

Thanx alot guys
DJ
1 - 8 of 8 Posts
you need to get the right single wire O2 sensor for the motor. and your idol should be around 600 rpm.
check your O2 ground with an DVOM. it should be lessn than .50 ohms right next to the sensor.
check the resistance of the TPS also it should be around 5v or 0V im not sure what one.

o and your battery is probaly dead from you trying to start it a bunch of times.

if you cant get the O2 ground good use a jumper wire and hook it to the houseing of the sensor and the ground on your battery.
dopeassjackson said:
you need to get the right single wire O2 sensor for the motor. and your idol should be around 600 rpm.
check your O2 ground with an DVOM. it should be lessn than .50 ohms right next to the sensor.
check the resistance of the TPS also it should be around 5v or 0V im not sure what one.

o and your battery is probaly dead from you trying to start it a bunch of times.

if you cant get the O2 ground good use a jumper wire and hook it to the houseing of the sensor and the ground on your battery.
Thanx for the advice on the 2 sensors, I will def check that. As for the battery, I know I killed it, but it was a new battery, so I put it on the charger and it was charged in 15 minutes. I think the starters shot. I pretty much pulled this car out of a junk yard where it sat for like 3 years. The starter didnt look that pretty when I pulled it off the old motor. Im gonna check the solenoid if I can find some time today.
Thanx again
DJ
stick that battery on the charger with a low amp over night to get it fully up.
Since you said the starter wasn't looking good at all when you pulled it and because it wasn't cranking at all you should give that a try. Definitley replace the O2 sensor, and clean the MAF sensor as well just to be safe.
The starters shot. Are the sohc and dohc starters the same.
gtp420 said:
The starters shot. Are the sohc and dohc starters the same.
LMAO, Thanx man, I was gettn on to ask the same thing. Yeah me and ^^^^ took the starter out and all that was in it that was left of the brushes was soot. So the starter has def taken a pooh.
As for the O2 sensor, I tested for resistance and read 0. So im guessing its good, I think Im gonna replace it anyways. Im hopin if I clean and check the stuff above, it takes care of this running rich and idle fluctuation.

Thanx
DJ
1 - 8 of 8 Posts
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