Dads89c4

So my dad purchased a 1989 corvette with a rod knocking in the l98. We decided to install a zz4 we found new in crate, install went flawless. We install Hedman long tubes and a maximizer exhaust true dual. Everything went perfect and the car sounds amazing. Now the issue we are having, the a/c heat panel is dead so you can't read what's going on, the fan will not shut off on radiator. The biggest problem is the cooling gauge sensor, it shows the car running at 240 degrees, won't come down at 80 mph and remember the fan is still on. So we pulled over and checked the thermostat housing with a heat gun and found it at 190-195 radiator at 183 and the heads at 205. The only thing under hood that was 240 was the coolant sensor passenger side block. We wrapped the sensor and it helped for a little bit, is it possible the long tubes are heat soaking the sensor? The one crazy thing that I don't like is when dad put the intake on he put the block offs on the front instead of the rear. His factory service book says front, so he did front could that cause the issue? From my understanding they are for holding coolant longer in engine so I wouldn't believe it would cause a issue. I don't want to beat a dead horse but this is driving us crazy, the sensor is a new professional sensor he purchased from the Chevy dealer since ac Delos discontinued them. Any ideas will be great on fixing issue. Thank u in advance

PatternDayTrader

I thought the coolant block offs go to the REAR. Keep bumping this thread to the top until you get a firm answer, and stop driving the car. In fact I thought there was discussion (within the last few weeks) about how the manual is wrong on this issue.

Dads89c4

Your right there is, but my dad did not know nor did I. From what I have seen they shouldn't even use them to start with. How do u keep bumping to the top? This is my first time on this forum. Thanks for your reply also, I appreciate your time.

PatternDayTrader

Everyone gets burnt on service manual updates....if they don't have them. I do mean everyone. It happens.

Everytime you post somthing the thread bumps to the top of the list. I'm sure it won't be long before you have a solid answer.

Dads89c4

Ok, thanks again for your help. I don't see why the coolant block offs would cause a high reading on the gauge. From what I have read it just slows the coolant down going into the intake. Suppose to help hold the coolant in the engine longer for less of a chance of blown head gaskets

PatternDayTrader

I think what's happening is its slowing down the hot coolant flowing out the t-stat neck when the restrictors are positioned at the front. Obviously, this could be a problem. I could be wrong, but that's the question you need an answer to.

Dads89c4

http://www.justanswer.com/chevy/0v6e...le-intake.html

So just found this, looks like we're pulling the intake back off tomorrow. At least he hasn't burnt it up, we can fix it now.
Thanks for the help.

PatternDayTrader

Well it sucks you have a bit of extra work to do but now you know for sure. Make sure you post some pics of the car once your done and maybe even your thoughts on the performance of the zz4 engine. I for one would like to hear about it, and I'm sure many other here would too. The zz4 always looked good on paper...

Dads89c4

I will take some videos once we get it finished and re timed. He kept the tpi without the egr and had it worked and gasket matched. Thanks again for the help.

ghoastrider1

wouldn't you need a chip tune for that engine? I too would love to hear some 1/4 numbers or thoughts on its performance from the owners. Sounds like a fun vette.

Dads89c4

We are having a new prom and men-cal adapter done by sinister performance for the car. It needs the egr, and smog equipment removed and fuel and timing readjusted a little. Other than that even with the tpi on the car it is a beast. Revs up fast and has tons of power, will know more after we replace the intake gaskets. Should we leave the blockers off the intake, I have read a lot of post on hear about leaving them off. Anyone have any for sure data on whether its better to just remove them completely?

Dads89c4

Mem-cal sorry

Dads89c4

So update, pulled intake and removed gaskets installed new putting block offs in rear. Will have the fuel injection and distributor back in by weekend to start up. Hope this fixes it, will have pics up Saturday afternoon. Thanks for everyone's help.

PatternDayTrader

I'm sure it will be fixed after this relatively minor issue. Keep us posted on how things turn out ...

Dads89c4

Alright it's done and the temp is running at 195 at idle and looking great. Running way cooler than expected, but no arguments right now. ,gonna put some miles on it in the morning after these blow up storms clear. Oil temp still not working, we put a new sensor in today, will start trouble shooting next week. I will take some pics and video tomorrow and have them posted. One question has anyone repaired the climate control panel themselves? If you have did it work afterwards..

PatternDayTrader

That's great news Its up and running. 195ish is about perfect. Everyone fixes the hvac control head on the newer cars like 92 through 96 .... I'm not sure about your model year. Start a new thread and I'm sure you will find out ...

Dads89c4

Doesn't look any different than l98 but it's a zz4<br ><br > If you notice there are two oil caps<br ><br > Other side <br ><br > My daughter loves her grand dads vette<br ><br > Maximized exhaust tips<br ><br >

Dads89c4

So here it is waiting on the spark plug wire holders

aklim

2 things. That little girl needs to have a block of wood on the gas pedal just like "Short Round" in Indiana Jones.

Also, do you have 2 oil fill holes? Mine is on the rear side of the valve cover on the right and my left cover doesn't have the oil fill hole. Just curious.

Dads89c4

Has one driver side front and passenger side rear. I don't think granddad will let her drive it ever.