Whenever I start my 2.8 fiero in the morning (about 25-30 degrees F out) it runs for a sec then dies. If I step hard on the gas it knocks for a sec then revs up but won't stay running unless I warm it up for about 5 min... Any idea why this is? How to fix it?
Could it be anything else? I'm not using the temperature sensor/sender as I have an aftermarket coolant fan relay I hooked up. How can I test the Switch
you have a "port on the corner of each head for "coolant sensors? I put a mechanical gauge in one of mine at that point. removing the sensor in the manifold is Not the right way to go in my opinion. that probably Is your problem. how to test, put the correct sensor "Back in" and see if it still does it. I don't think you can test it "out of the car"
There may be deferent thermistor resistance values but I have seen one yet. Google thermistor resistance chart. The chart will show resistance related temperature. I believe that the wire terminal to the sensor body will show the resistance reading unless there are 2 wires to the sensor. I haven't tried the test.
[This message has been edited by LornesGT (edited 11-25-2013).]
The cold start injector only sprays fuel while cranking - if it runs bad after it starts the problem is something else.
The ecm temp sensor (yellow and black wires) MUST be connected for the motor to run right - the ecm will read -40 degrees and run rich all the time if it's disconnected. Replace the temp sensor and check for corrosion on the temp sensor teminals AND the 2 wire plug, I've had a couple corroded connectors on different cars causing bad readings to the ecm.
Another possibility for drivability problems (after fixing the temp sensor) is grounds to the motor/body - read this thread:
Looks like the first thing I need to buy is a new ECM temp sensor and figure out how to wire it. Also I looked at my grounds today in my engine bay and at least 4 of them (thick gauge) are broken connections. It looks like the PO just got mad one day and snipped all the grounds. So I have some work there which I hope explains why when I put my foot down hard on the throttle instead of revving it gurgles and knocks. Or I need to check my fuel pressure... maybe Mass Air reader.
Probably a dumb question but... Do you usually make your own grounding straps since it's just a wire with twe eye inlets on either side or do you purchase them? If I do make them, any specific material? And what locations? The link given above shows me one really good location but not all.
Definately fix any missing grounds - made the biggest difference in my driveability problems. You can make them yourself from 4ga wire & crimp eyes or NAPA sells ground straps ready to bolt on. The one that seems to make the biggest difference is from the timing cover stud to the right side of the body. There's other factory ones from the engine to the passenger trunk lid hindge and from the transmission to the driver side frame rail (all were missing on mine - cut when motor was replaced).
If the ECM temp sensor is missing you can get it and the connector at any parts store, most 80's/90's GM's used the same one. The wires should be close to the sensor location in the picture posted earlier, colors are yellow and black. Use heat shrink tubing on your wire splices to keep them from corroding later.
[This message has been edited by AL68 (edited 11-26-2013).]
Do I have to remove anything to get access to the temperature sensor? It seems to be tucked behind a ton of wires and hoses. Also what do I want to put on the threads of the Temp Sensor when I put the new one in?
[This message has been edited by Jecklen16 (edited 11-26-2013).]
You might have to move the egr solenoid for some extra room, I think it's bracket mounts to the stud you bolt the extra ground cable to. The first picture in the "grounds" thread will give you a good idea what's on the front of the motor.
Put some Teflon tape/paste on the threads (some sensors come with some sealer already on it), or a little sillicone if nothing else is available.
Okay so I bought a grounding strap and hooked it up, also I hooked up a tach filter to try and fix my tach issues. Neither of these worked and now my tach starts at 500 and bumps up 300 every time the engine turns over then once it starts it just spins clockwise and maxes out, so no idea what was going on there but the idiot who owned the car previously had no tach filter at all.
Back to the primary subject though. I found the Temp Sensor and it IS in the engine block but had 2 prongs sticking out of it with no cable/wire in site... the connector on the back looks broken which isn't a concern because I'm pulling it out and replacing it anyway but my biggest concern is that I cant seem to find the wire that goes to the temp sensor at all... what would my next step be?
Nevermind, I found the yellow and black wire connector, thought the female connector on it is the wrong size for the temp sensor I have so I will be buying new temp sensor connector wiring and splicing it in.
That's the connector that fits my new sensor. I think either the old one got smashed or the PO cut it out and put a diff one in. It has 2 wires connected to it, a black and yellow one so I believe its correct.
If there's 2 pins sticking out of the sensor it sounds like the head of the sensor broke off, they should be recessed inside. The original plug could have been hanging down & rubbing on the belt?
You should be good with the plug in the above photo & matching sensor.
Disconnect the battery before fixing the sensor - will clear the ecm memory
I put the new Coolant temperature sensor in and got all the wires spliced correctly. Hooked it up with the battery disconnected, reconnected everything when finished and it runs amazingly now. When I floor it, it doesn't gurgle or knock. It starts up cold and stays running like it has been the whole time! Thank you everyone for your help!
