LT1DG

Wsup guys, so I have questionable issues going on, and can't seem to figure it out. I have 95 trans am and just got my heads rebuilt due to them being warped. Added to that, new water pump, new optispark, new timing chain set with a cc502 cam, along with the supporting valvetrain parts. It's not tune yet, and should be ina couple of days by solomon. So here the first issue I've experience since getting back from the shop, occasionally after driving on the freeway with a little stop a go traffic I'll park somewhere and turn the engine off, coolent starts shooting out the resorvoir. Temp Gauge is in the reds while driving , but I debunked that problem before I got it out the shop. The Mechanic temp gun read 170 after they let it idle for a hour, at that sametime the gauge was all the way in reds. It's clearly not overheating. I did have a fail safe 160 thermostat install and when I checked it was stuck in fail safe position, I've read that fail safe stats don't do well with lt1s. So I replace it with a stock 180 thermostat and set my fans back to 180 in the pcm with hypertech. I also replace the sensor on the waterpump cause it seem like whoever reassembling the motor they didn't put it in all the way cause i seen coolent seaping from under it and dripping on ground and it seem like it was damaged to. Ever since then, coolent actually stays in the radiator now and no boiling over out the resorvoir anymore after like 30- 35 min drives (In city traffic that is) but then again I haven't took it on a long freeway drive yet. I've taking it on freeway drive but only for like 10mins. And what's weird is now my temp gauge (Even tho I debunked it) doesn't rinse up as fast as it did before, i fact it stays at least around the 175- 195 range and occasionally goes up alitte bit more, that I dont understand. Alrite second issue, since the cam install I've had ses light, (I'm aware that cams can cause ses light) but the weird thing is, it goes on and off especially after replace my iac valve, (stuck open) and tps, air temp sensor. When I warm up from cold start ses is not on, but when the lopes start kicking in the light pops up, so here the weird part though while driving the light is on, but at a stop it goes off but once I hit the gas bam it's back. I even did the iac reset procedure and the light goes off for awhile up until I start driving. I know its not tune yet, but it drives real good, lots of power maybe alittle lag here and there. But it's not tune so that's understandable. I just need some answers, and some guidance to narrow down things with this lt1 cause what if the cam is not throwing a code and it's something else. I was thinking o2 sensors, cause the way the light goes on and off and when warming up it comes on later on in warm up (I'm assuming OL is when it comes on) I know o2 sensor starts to send signals in that open loop phase, could be wrong. Any information is good, especially the OG guys who knows everything about the lt1 lol. I need you guys. Thanks

ss.slp.ls1

iTrader: (36)

Exactly what code is being thrown when the SES light comes on? As for the temperature, I would try properly bleeding the system and trapped air is a common problem.

LT1DG

I haven no clue, I need a scanner. One thing I do know, it wasn't there before the cam was installed or the ppl who put the motor together bang up some sensors. Idk. And I did try bleeding it, but I saw that it was a full stream so I figured no air

Jon M

I had coolant coming out of my reservoir too after heating up. My issue was I over filled it by half a gallon. Since then, about half a gallon poured out and no more issues. Did you try the sensor in the driver’s side head? That is your dash gauge sensor. Try running a scan with Scan9495 or EEHack

atlantadan

You are just shooting in the dark without a scanner. Get a good ALDL cable (NOT Red Devil River), download Scan9495 and eehack, hook it up and datalog it. This will also determine the cause of the SES light. Or you can keep throwing parts at it until you randomly hit on the issue

Jon M

Why not Red Devil River? I have one from there and it works thus far...

LT1DG

Update guys while going thru the fuse box in the engine bay I saw that my air pump fuse was blown, so put a new one start the car for sec and what do you know it's blows again. Air pump bad? That will set ses light right?

atlantadan

Yes, that will trip the light and no way to know for sure if the pump itself is bad. Could be. Could also be a wiring issue. If you had a cable you could disable the air pump. It is not needed to be smog-legal.

RDR cabes use counterfeit FTDI chips. Updating the FTDI drivers will alter the chips (if not nuke them directly), which will eventually zap your PCM when you try to burn a tune. They may work ok in a read-only state, however. In addition, they do not work well, if at all, on b-body cars. The common thought is that its due to some of the other background chatter that is present on the b-body datastream, but nobody really knows for sure. There are multiple users that report flash errors (which brick the PCM), unstable datalogging connections, and other issues.

This guy makes really top-notch cables that perform with zero errors on all scanning/burning platforms. Pricey, but cheaper than a PCM.

LT1DG

If that's the case I will unplug it and replace the old with new fuse. I'll let you guys know how it does after.

LT1DG

Yeah, everytime I turned off my car after a freeway drive I'll hear the bubbling sound thru the inside of my car then coolent will flowing like crazy out the resorvoir. It doesn't do it no more thought.

Vicious95Z28

iTrader: (1)

And if you're an OBD1 '95 guy with the 16 pin?

atlantadan

Not sure what you are asking. If you're looking for a non counterfeit cable - Link

BALLSS

OP

if the shop that did the work did not bleed the air from cooling system, it will over heat. The Gen 2 LT1 is unique to all other SBC because of its reverse cooling and requires bleeding. Ideally this bleeding is done without puking coolant on the Opti....which will then cause other issues.

Stop chasing why you have drivability or idle issues before getting a tune

and as mentioned get a way of reading data. scan9495 is one option but requires a "cable"...of which you need the "right" one as noted by Atlanta

LT1DG

The shop that did are very knowledgeable on lt1 and aware of the the reverse flow feature. They bleed it twice because the gauge was showing high temp when it really was inaccurated. I even bleed it myself to make sure and a full stream of coolent came out no air. I had to replace my reservoir not to long ago because it had a hole. When I put everything together I may have put to much in the reservoir. My airpump was my SES light issue but I do need a scanner for future reference.

LT1DG

Wsup guys so here the update I changed out my fuse for a new one and unplugged the air pump. Let it idle for 20mins and no check engine light, usually it pop up within 5mins of cold start. I also change out the temp gauge sensor in the head. It's seem like it was broken cause I was able to spin the black part of the sensor in circles, the new one doesn't do that. I'm assuming that mean it was broke right? Lol. Btw I appreciate the help guys, love this forum 👍👍👍 even tho I don't use it often, which I should.

LT1DG

One more thing guys and I know this is off topic so the performance transmission bottom right, how do I know when it's on or off. Is it a on when amber is light is on or off?

LT1DG

Wsup guys so i think i might have another problem going on. While driving earlier my temp was climbing slowly while driving but at a stop it would stay put. But again when i start driving it slowly creeping up. I just switch to a 160 stat yesterday and set the fans to come on when they should. When i got home the temp was between 210 and the line after , i let it idle (Fans are on) and gets to the reds so i shut it off.i popped the hood and i can hear coolent going back into radiator. But no boiling over thru the reservoir this tim. Even to the touch the motor didn't feel that hot. That wasn't even a long drive too. Im confuse guys, i drove it this morning and it didn't even rise that fast, it was 170 180 steady range. What do you guys think? Air in the system? I mean last month i had to replace my heater hose cause it blew coolent everrywhere. I lost a lot coolent cause the radiator was damn near empty. I filled it up after replacing the hose but didnt bleed it correctly.

LT1DG

No answer?

ss.slp.ls1

iTrader: (36)

I would rectify this first.

LT1DG

​​​​​​I tried a couple of days ago. So here what I notice while trying to bleed the system for 35mins That the coolent level in the radiator kept rising, but didn't drop. The upper hose that connects to the thermostat didn't have pressure or wasn't hot like the other radiator hoses, I can literally squeeze it. My temp stayed at the 165-170 range the whole time idling. I took it for a spin, drove it for 15mins and notice everytime I accelerate temp gauge slowly goes up, but when I stop temp stays at a steady range and doesn't move but once I start driving it slowly goes up. When I got back the temp was a shy under the middle line (210) I let it idle 10mins after parking and the gauge stay under 210 which is odd. I also squeeze the upper hose and had pressure but not that hot like the other radiator hoses.