Anybody Know what Is Wrong here?

[crunchie12268]

My has been running 'warmer' than usual according to my gauge... but get this... when I push on the brake or turn on the headlights or roll up the windows the gauge goes up... I put on my stock underdrive pulley for the water pump and it has a new radiator, water pump, hoses... and it is running warm... Like Straight over on the NORMAL gauge and a little above.. but it doesn't do it until I drive it for a while... It is running normal then it starts to slowly get warmer.. then when I get on it, it starts to get hotter and doesn't cool down very fast.... anybody know whats up???

 

[crunchie12268]

I don't suppose it could be a sending unit could it?

 

[Legendary]

I don't suppose it could be a sending unit could it?

That or maybe a bad ground?

 

[dromeda]

I'd hate to suggest changing the sending unit and have it turn out not to be that, but that's what I would try. How many miles are on it and what kind of fan do you have?

 

[crunchie12268]

The sending unit has 104,000 miles on it I am assuming... the fan is the stock fan with the clutch and all..

 

[crunchie12268]

I have changed the thermostat (180), the radiator, waterpump, took off the water pump pulley put on the stock, radiator cap, hoses. Is there anything else it could be?

 

[2000xp8]

The gauge is a piece of crap, mine did the same stuff. I got an autometer to replace it, the stock gauge is worthless.

 

[mac7290]

I had the same exact problem. Mine was the ignition switch. $12 for a new one. Fixed it.Sounds strange but true. Mine would go up at least a notch on the gauge. Turn my A/C on high and it would instantly rise, turn it off and would go back down. Any time I put a load on the electrical it would go up. Hope this helps.

 

[HISSIN50]

remember that gauge sender wires go through the voltage regulator before hitting the gauge itself. if the regulator is not up to par, you can see variations and such.
not that it is the issue - just something to keep in mind if all else fails. it should not really matter though - 2000XP8 is spot on. get a real gauge and know for sure what is goin on.
good luck.

 

[2000xp8]

Now that you've had this problem, trust me, you'll never feel comfortable with the stock gauge again, so don't spend alot of time trying to fix it. I think you can get an autometer mechanical FULL sweep temp gauge for around $50-$75 bucks on ebay. You'll know what your car is really running at all times, and as you modify it and it ages you'll be thanking me later.

 

[04sleeper]

Now that you've had this problem, trust me, you'll never feel comfortable with the stock gauge again, so don't spend alot of time trying to fix it. I think you can get an autometer mechanical FULL sweep temp gauge for around $50-$75 bucks on ebay. You'll know what your car is really running at all times, and as you modify it and it ages you'll be thanking me later.

Very true. One of the first mods on my car was mechanical oil and water gauges. They do not cost much and are cheap insurance for that motor you are dumping money into.

 

[stang619]

Did you ever find out what the problem was crunchie??? Ive been experienceing similar problems. thanks

 

[liv2ride]

Very true. One of the first mods on my car was mechanical oil and water gauges. They do not cost much and are cheap insurance for that motor you are dumping money into.

I second that. I was having trouble too after changing to a high volume water pump and 180* t-stat. I replaced the sending unit because it was cheap, about $7. That helped slightly but still did not make me feel comfortable because the reading was different since I changed the pump and t-stat (reading too hot). Then I bought a two gauge Auto Gauge kit with mounting bracket. The two gauges are mechanical; one for oil pressure and the other is water temp. I now know that I am running nice and cool, compared to the reading on the stock gauge.

Usually when the temp gauge starts reading erratic chances are that the oil pressure and voltmeter is also reading incorrectly. This is typically due to the failing or weak Instrument Voltage Regulator (IVR). To fix this problem you need to buy a replacement and tear apart the entire dash to get to the backside of the gauge cluster. Personally I rather buy and install after market gauges that will be more accurate by a good margin.

Aloha

 

[JB66]

They stopped using an IVR in 90 or 91 for the gauges. My opinion would be a weak ground between the engine and the firewall. Lots of people forget to reinstall it on the bellhousing bolt when they put an engine or tranny back in, then say they'll get to it later.

 

[jrichker]

They stopped using an IVR in 90 or 91 for the gauges. My opinion would be a weak ground between the engine and the firewall. Lots of people forget to reinstall it on the bellhousing bolt when they put an engine or tranny back in, then say they'll get to it later.

Another vote for a bad or missing engine to firewall ground.

Any car that has a 3G alternator needs a 4 gauge ground wire running from the block to the chassis ground where the battery pigtail ground connects.