Aenglish0516

I need some help with my Z28

When I get up to drive it after it has been sitting for a day or so, Ill start the car up, it makes a popping noise and I have to rev the car up to about 2500k for a few minutes, otherwise it boggs down and will shut off.

BTW: This crap didn't start until I put some ''gunk'' on the engine and sprayed it off at the carwash...Idk if I got something wet or not

ALSO......

After driving for a little while...the temp gauge will red line (260) especially when I'm at a complete stop. The engine doesn't smoke, and I haven't seen a coolant leak...and the low coolant light is on, but when I fill it, it doesn't go off

If someone knows what the issue is, please let me know asap, and thanks in advance for your help!!!!

nintythreeZ28

optispark is screwed... hate to do that to ya.... im guessing its an lt1. it would help if you had a signature with the details about your car

JackBlack95

I know nothing about nothing, but sounds like opti.

Rij1

Water might have got into the distributor/cap, It's common in the 94-95 lt1's for water to easily get into the opti-spark Distributor because its not sealed or vented to well and what water/moisture gets into it doesnt really get out of it.
Does the car idle/drive the same after it is warmed up?
When did your temp problem start? Before or after you washed the engine?
You may have to burp the cooling system with the 2 venting screws.
Try and put more info about the problem you have so more answers will be given.

jit11375

yea i'd have 2 say it was you opti as well...94's werent vented at all, unless you have an msd. have an ses light? Scan for codes, thats always a good place to start

Aenglish0516

How much does it cost to have something like that fixed???? That worries me

Aenglish0516

After the car warms up, it doesn't bogg down like it does when you start it, it drives fine. The temp problem has been an ongoing problem, did not get any worse or any better when the engine was washed, and I have NO CLUE how to burp the cooling system....can anyone walk me through it?

raroz28

go to shbox.com and look for the coolant procedure.

Could be a coolant temp sensor. The one in the water pump, not the head. o2 sensor could also be bad.

Rij1

It can be very expensive if you cant work on it your self. Parts can be $150 for the distributor and $175 for the cap and rotor from a place like autozone but these parts are cheap. you would need other minor parts also.

Hve some shop scan the car.

Here is the 2 venting screws to get the air out of the cooling system.
http://shbox.com/1/bleeders.jpg
what I would do Is remove the radiator cap and then loosen one of the screws up or remove it then add water to the radiator. when the water starts to come out tighten the screw back down. then do the same with the other one. then do it again after the next time you drive the car but not when it's hot. If that dont help the temp problem then you have another problem.

Read through here
http://shbox.com/1/4th_gen_tech2.html#radflush

jit11375

if u pay to get your opti changed it can be quite costly, the part if you get a delphi unit off ebay is 350-400 dollars, and labor is a bit intensive...i was quoted 1500 parts and labor...but i got the opti for 365 off ebay and had a couple friends help me out and it all worked out great. if you can do the work yourself...its not too too expensive..paying someone to have it done is a different story

bw_hunter

Having the opti replaced is expensive.

That baloney about the early distributors being prone to water intrusion just isn't true. The venting was added to remove ozone and extend the life of the high voltage section.

However, a distributor cap is a tune up item and show be replaced on a regular basis. It sounds like yours is due if it gets wet and stumbles, then works better as it dries.

You need a scaN to tell you what is going on with the cooling. It could be as simple as air trapped in the system. Your owners manual tells you how to bleed the air out of the system.

raroz28

opti swap isn't hard. Buy it and do it yourself. Get a GM opti.

Drain coolant
Remove water pump
Remove harmonic balancer
Remove opti

It's really that simple.

Reinstall opti
Reinstall harmonic balancer
Reinstall water pump with new gaskets
Fill coolant

Bleed coolant and you're done.

jit11375

yea there r plenty of write ups on it, and it is really that simple. seems like a hard task to undertake by urself, but really isnt too bad

L.dookie

+1 easier and cheaper than an opti. if it runs fine once it warms up it's possible your coolant temp sensor is screwed up. take it to a shop or something and have someone look at the car, just make sure they know how to work on an LT1.

nintythreeZ28

lesson hard learned. when cleaning the engine bay, or doing anything to these lt1s you need to be extremly careful about the craptispark, these are prone to going out with water. i had mine give me a little truble backflushing the heater core (a tiny bit of coolant got on the opti) after about 5 minutes of misfire it was fine (water dried) but this is not always the case, and im sure it hurt the life expectancy of my opti. On the plus side i can survive these Missouri winters with hot heat.