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I love my Chevy Chevette!
Posts: 1
Joined: 05/14
Posted: 05/08/14 12:29 AM

I have a 94 z/28 with lt1 in it since I have had the car it has allway right a little high on temp plus use some water what do you think it might be the cause of this  

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V-6 Camaros rule!
Posts: 36
Joined: 10/13
Posted: 05/08/14 07:52 AM

what temp thermostat do you have..  the LT1 calls for a 180F thermostat verses the earlier L98 and almost everything else that uses a 192F thermostat..

if you have removed your thermostat.. you will have a runaway cooling system that will be almost impossible to cool...

with a thermostat properly installed.. the coolant circulates inside the heads then the engine block in the LT1 optispark motors picking up heat until it reaches the opening point of the thermostat..  then it exchanges the hot coolant in the heads and engine to the cooler coolant in the radiator. the thermostat cycles closed stopping the flow into the radiator.  as soon as the coolant is exchanged the radiator fans are commanded on usually for a timed session.. as the coolant temp sensor is in the water pump.. it cannot tell how hot the coolant in the radiator is..

so.. a few things.. check your thermostat.. or get in and change it.. put a 180F thermostat in there.. don't mess with a 160 trying to cool it off unless you are going to figure out how to reprogram your pcm to command the cooling fans to cycle at a lower temp and recalculate the coolant temp verses fuel curve..

make sure that your cooling fans are working properly. no squeeking motors..

perform a voltage drop test to verify the various grounds and power connections are working as designed.. you would not believe how many slightly corroded ground connections and power connections i have to clean and reassemble..


perform an additional 2 tests..
5, positive battery post to several of the fuses in the under hood fuse/relay box i think there is one in that year.. i know all the later ones have them..  0.04 volts DC MAX..

6. positive battery post to the alternator output stud. 0.3 volts or less,

you might also want to change the engine coolant temp sensor and pigtail..  they have been known to drift out of calibration over their years of service. pickup a duralast or wells SU102.. the kit is under 20 bucks.

SU102 Ectsensorgm Zps9f2d9178

a few more things.. with LT1 optispark motors. examine your ignition coil..

Dbbc7910 B2b1 4009 9900 9E95cda84a7b Zpsb8436a2a

a mechanic used to have a pair of squirt bottles. one with some salt water. the other with distilled water.. he sprayed a little salt water on the coil.. if the engine died.. he washed it off with distilled water and the engine could start again to prove to the customer the coil was leaking..  

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