How many O2 Sensor are on a 350 Tbi ? 87 k5 blazer

[K5Blazerboy87]

Hi guys I'm thinking it's time to replace the O2 Sensor idk if there's only 1 or 3 not sure because I went under it I only saw one but looking at recent videos they said there are normally 3 ? Does anyone know how many O2 Sensors are on a 350 Tbi? 87 k5 blazer

 

[Moonsaber]

Hi guys I'm thinking it's time to replace the O2 Sensor idk if there's only 1 or 3 not sure because I went under it I only saw one but looking at recent videos they said there are normally 3 ? Does anyone know how many O2 Sensors are on a 350 Tbi? 87 k5 blazer

Mine only has one, and it was not originally a powered one. When I bought mine it had one about 3 feet down the header, and altered to a 3 wire sensor.

From what I have been told, it originally had a 1 wire sensor right on the stock manifold.

Who says there are 3 on an 87?

 

[yevgenievich]

Should be only one

 

[K5Blazerboy87]

Well I watched a video but it looked to be newer car but I'm assuming mine bad cause I'm thinking it could be cause of poor gas millage plus it's never been changed before so.

 

[Derick C.]

Yea should have 1 in the driver side manifold

 

[1987 GMC Jimmy]

I'd consider that, but I would look at the coolant temperature sensor, too. I'd also see how the fuel's spraying and if the plugs are fouled. It could be ready for a tune up or the TBI could need a rebuild, especially pertaining to the FPR diaphragm. Is it running rich?

 

[Georgeb]

I would like to add, also be sure you have a good working 195 degree thermostat and the ground by the coolant temp sensor on the intake manifold is good and clean. The temp sensor on the intake is the one that tells the ecm how warm the engine is and adjusts fuel metering.

 

[Rusty Nail]

How much gas mileage does my truck get?

 

[CSFJ]

How much gas mileage does my truck get?

1 billion mpg

You must be registered for see images attach

 

[Rusty Nail]

Dude.
When I saw you had replied, I knew it was gonna be somethin funny but man! I didn't see that much funny comin. Holy crap that was hilarious!

 

[CSFJ]

Lol. First thing that popped into my head. Just had to grab the image online.

 

[adamj]

I have a stock 350 TBI, it is just one O2 sensor, found in the driver's side exhaust manifold. There is just one wire, which I guess is an old design, so no heater to get it up to temp faster so it can start reading accurately.

 

[smoothandlow84]

My 87 motor tbi 350 has only one o2 sensor and a single wire connection.

 

[K5Blazerboy87]

Idk I did a tune up last summer about 7 months ago got new plugs I wanna get new thermostat and O2 Sensor so yeah
See if that's the case

 

[K5Blazerboy87]

I mean I Filled up all the way on 30th of November and I drive about 5 miles a day in whole week Monday through Friday and it's 21 st of December now and I'm just a tiny bit over a hafe a tank ? I mean idk if that's good gas mileage or not for my truck