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can sombody tell me the locationds of the sensors on a 91 3.1 V6 camaro.
I'm specificly interested in the Knock sensor,and temp sender.
9 need exact locations inside block, outside block, obve somethnig , underneath something.
everything.
Here's the list.
Knock sensor: Passenger's side of block, underneath the exhaust manifold, next to the starter.
Temp sensor (coolant): Front top of engine, underneath the throttle body. Has black and yellow(?) wires running to it.
Temp sensor (intake air): Screwed to a nut welded to the side of the air cleaner can. Probably on the front side of the can, yellow and purple wires.
MAP sensor: (I don't have one, not really sure, if wrong, someone correct me): Driver's side of engine bay near brake booster. Has a green three-wire plug and a vacuum line running to it.
O2 sensor: Underneath the car, in the engine crossover pipe, near the passenger's side lower A arm. Single black wire running to it, 7/8", will probably need heat to replace.
Throttle position sensor: Passenger's side of the throttle body, has 3 wires running to it, and is non-adjustable for the most part.
Idle air control motor: Above the TPS, has a four-wire connector, 2 blue and 2 green.
Oil pressure sending unit (also sensor): Near the oil filter on the driver's side, has 3 wires running to it. White, orange, and black.
Any others, I've forgotten, feel free to ask. Also, your ECM (engine computer) is up under the dash on the passenger's side of the car. You need to remove both lower panels to get at it. (Just in case you needed to know)
:edit: Just noticed you're across the pond. (Swap the driver's side location for the TPS and the knock sensor).
MAP sensor: (I don't have one, not really sure, if wrong, someone correct me): Driver's side of engine bay near brake booster. Has a green three-wire plug and a vacuum line running to it.
Im not sure of the wire colors, but the MAP sensor is on the pass. side bolted to the lip on the firewall. Almost right above the ign coil.
There is another coolent temp sensor in the front of the driver side head.
I'm looking for a 1 wire ( green ) sender unit that goes to the gauges.
( also, does the knock sensor bolt into a waterplug ( I mean, if i get it out, will I get a shower of water over me ? same goes for the temp sender to the gauge.
You didn't say anything about the temp sender.
But, anyways, the sender is the single wire unit he has in the second pic above, the one with the funky looking connector and the green wire running to it. Your 3.1 does NOT have the fan switch in this same position on the pass side head, as it completely relies on the ECM and the CTS for switching the fan relay on and off.
or you put the new one in place of the old 1.
or you drill a hole in your block. or in another place where there is running hot water from your block. ( do not place it behind your thermostat since it wont measure the water then till the thermostat opens)
My 91rs 3.1 temp sensor is front driver's side right behind the a/c punp it is brass with a flat like top with a slide on kinda 90 degree connector. This runs the gauge only nothing else that I know of.
yups, the small 1 near the collector only runs the gauge.
already found that 1. changed he senderwith the new 1 rom nordskog together with giving it an all new wire to my dash.
I can tell you, this thing is accurate
with my 180 thermostat. on the freeway, my temp is between 179 and 181 degrees.
thats less then a 1% error read.
is this the same for the 2.8 v6's to? cause i think i know where my coolent temp sensor is...but how to i get to it to change it?
You can either do it the hard way by removing the upper half of the plenum or get yourself a flex-joint for a 3/8" ratchet and use a 5/8" (please tell me I'm right) deep socket to get to it from the driver's side of the engine.
And for those newbies out there, the 2.8 and the 3.1 are the same engine with the exception of the computer and fuel injection system, crankshaft, and pistons.
That one is under the TB I believe on the intake manifold and the one that kicks the fan on is on the back of the passenger head.
Hi -
I'm in the middle of changing a head gasket, and I found this sensor (sender?) was completely broken--literlly, the top half of the sensor was completely missing, and so I don't know what the lead coming off of it looked like, or where it ran to. I don't even know if I need the part called Coolant Temp Sensor or Coolant Temp Sender---they are both the same size, but the connection is different. (BTW, the previous owner has hardwired th fan to run all thetime, probably because he was too lazy to replace the sensor.) See pics here: https://www.thirdgen.org/forums/tech...me-sensor.html
Can someone please post a photo of what this (the temp sensor/sender connection on the back of the passenger's side head) is supposed to look like?
You're looking for the 2-wire sensor in the pics above (next to the thermostat housing, top pic). The connector looks almost the same as does the connector for the air temp sensor in your air cleaner can, except it's black instead of gray.
:edit: It may not be that your fan has been hardwired to run. Your ECM may just be running the fan because it doesn't know how hot the engine is. Also, expect cruddy mileage and nearly black exhaust, as the ECM will be adding fuel because it thinks the engine temp is below zero (IIRC, anyways). I worked on a 95 Grand Prix that had this problem.
hey guys, i ran into a problem with this, i got the old unit out but now i cant get the new sensor into the hole?, it just sits and spins on me, any help?
hey guys, i ran into a problem with this, i got the old unit out but now i cant get the new sensor into the hole?, it just sits and spins on me, any help?
You'll want to pull the upper plenum off and get it started by hand... DO NOT use a wrench to get it started as you could strip out the threads in the intake by cross-threading the sensor with the intake threads (if you haven't cross-threaded it already).
BTW, my mistake... It's a 3/4" wrench or socket you use on the CTS.
Check the 2 sensors side by side, comparing the threads. And not just 2 threads, check the whole length from the thermistor end (in the engine) to the part the wrench sits on. If there's nothing in the way and it's not going in, you probably have either bad threads in the intake or the wrong replacement sensor, or some guy at the machine shop that made the sensor body screwed up the threads good.
checked the threads they are right, the replacemnt is alittle longer and alittle wider, i just dont understand, the original goes in fine but the new one wont go in.....
If the new sensor is wider (at the threads), that's why it's not going in. It's not going to fit in the hole unless you rethread the hole larger. Take it back, take the old one in, and tell the guy you need one just like it. Don't rethread the hole larger as you may need another replacement sometime that is the right size and it then won't fit.
Another thing: Get in the habit of NOT using thread tape on the coolant sensors, with the exception of the knock sensor (that you had in the 91 by the starter). The gauge sender, in particular, grounds through the threads into the cylinder head, and the tape can mess up the resistance readings (you can possibly get away from it in the intake sensors but I wouldn't advise doing so on a regular basis to avoid a habit in case you get stuck working on a late-model car that has the all-in-one gauge and ECM sender). Get a wire brush and clean the tape off (preferably brass). Just tell them you bought the wrong part (or they made a mistake and gave you the wrong part in the right box... Had that happen at NAPA a few times).
ok, i have the recipet and everything but my step dad did the tape when he was lookin at it today when i was at school, i didnt have to take the plenum off to get the original out...
ok, i have the recipet and everything but my step dad did the tape when he was lookin at it today when i was at school, i didnt have to take the plenum off to get the original out...
Or, maybe if you get lucky enough, you can find the end of the tape and unwind it...
I bought a temp sensor the other day and it already had red tape on it. Is that normal. It is like half way up the threads. When I read this and you mentioned not to use tape I thought it was odd. Got it at The new O'reilly's they took over checkers.
I'm reviving this old thread to present the temp gage and drivability problem I'm having.
Here are the facts:
1988 Camaro with 2.8 V6 and manual transmission
Temp gage readings are erratic
Start motor and let run at idle until fan kicks on (about 15 minutes)
Temp gage comes up only slightly (still reads at nearly the bottom of range)
Drive for 10 minutes and motor runs strong - gage does not come up to middle of the range like it should if operating normally
Gage needle then drops to almost absolute bottom of range
Deliberate, aggressive hard-acceleration --- and then as motor reaches peak of powerband (yeah, 2.8 stock motor "powerband" ha-hah) the motor stumbles hard
stumble feels like fuel to all cylinders has been momentarily shut off, then motor "comes back" - severe "whiplash" type driving sensation as motor rapidly dies-and-recovers
This condition will persist until temp gage "recovers" and starts showing believable readings
When gage runs in the mid-range to just slightly above mid-point, this stumbling problem never happens, and motor runs strong
Problem only occurs when temp gage is reading at implausibly-low reading
Question:
Could the drivability issue be the temp sensor (or a bad connection at the temp sensor) sending bad info to the ECM, and then the ECM causing the fuel delivery system to provide incorrect fuel/air ratio such that this stumbling would occur?
I also sometimes get the stumbling very soon after the motor has "warmed up" when I'm just driving the car gently at light throttle.
The thing that keeps jumping out at me is that the stumbling problem never happens unless the temp gage is just slightly above the bottom of its display range. The maddening thing about it is that the gage can drop down into that low range when there is no possible way that the actual temp could the same as what the gage is showing.
I'm reviving this old thread to present the temp gage and drivability problem I'm having.
Here are the facts:
1988 Camaro with 2.8 V6 and manual transmission
Temp gage readings are erratic
Start motor and let run at idle until fan kicks on (about 15 minutes)
Temp gage comes up only slightly (still reads at nearly the bottom of range)
Drive for 10 minutes and motor runs strong - gage does not come up to middle of the range like it should if operating normally
Gage needle then drops to almost absolute bottom of range
Deliberate, aggressive hard-acceleration --- and then as motor reaches peak of powerband (yeah, 2.8 stock motor "powerband" ha-hah) the motor stumbles hard
stumble feels like fuel to all cylinders has been momentarily shut off, then motor "comes back" - severe "whiplash" type driving sensation as motor rapidly dies-and-recovers
This condition will persist until temp gage "recovers" and starts showing believable readings
When gage runs in the mid-range to just slightly above mid-point, this stumbling problem never happens, and motor runs strong
Problem only occurs when temp gage is reading at implausibly-low reading
Question:
Could the drivability issue be the temp sensor (or a bad connection at the temp sensor) sending bad info to the ECM, and then the ECM causing the fuel delivery system to provide incorrect fuel/air ratio such that this stumbling would occur?
I also sometimes get the stumbling very soon after the motor has "warmed up" when I'm just driving the car gently at light throttle.
The thing that keeps jumping out at me is that the stumbling problem never happens unless the temp gage is just slightly above the bottom of its display range. The maddening thing about it is that the gage can drop down into that low range when there is no possible way that the actual temp could the same as what the gage is showing.
Advice?
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My guess? Air bubble in the system. Keep in mind you're dealing with 2 temperature sensing units. One for the gauge in the cylinder head and the other in the intake manifold. It's highly doubtful both of them are failing in the exact same manner at the exact same time. There has to be another issue in the system. Take the 2-wire sensor out. If coolant doesn't come out of the hole, you have an air bubble. Any air pocket in the system can cause the readings to be abnormally low, and lower readings from the actual ECM sensor can throw the system to the RICH side.
Since I work at such a blistering pace, I seem to find it necessary to revive this thread every three or four years.
I swapped gauge-clusters on my V6 car today. Replaced the V6 cluster with a V8 cluster. Temp gauge needle was beyond buried. But, instead of immediately examining the needle closer, I pulled up this old thread, and I poked around under the hood until I found the green wire mentioned above. Single green wire. Connects to a spade-type connector on a screw-in sending-unit on the front, driver-side of the motor. Mine had no fancy cover on the connector. Just a bare spade-connector that looked to be intact. Connects to a sending unit that looks like this:
Instead of molesting the green wire, I pulled the clear bezel on the gauge cluster and freed the needle on the dash gauge. I'll report back in three or four years.
I'm still a little confused about the temperatures that get reported to the ECM.
I'm getting my feet wet finally with TunerPro.
Not sure why I've got two coolant temperatures (different readings naturally) reporting to the ECM.
02-22-2008, 08:22 AM
