Lt1 weird issues
Thread Starter
Launching!
Joined: Apr 2019
Posts: 206
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From: Bay area
Are you sure you have the correct temp sensor in the w/p? That is a different part number than the one in the cylinder head. I'm guessing the wires pictured are to the water pump temp sensor? You need to follow those to see if they are damaged. It's also possible the bare wire is grounding out causing your erratic readings. Simply wrap electrical tape around bare areas for a quick fix and see if that helps.
That picture is the wire coming from iac sensor on the intake, but I see that the temp sensor also mates with same harness. I would think that would cause issues to the temp sensor cause the wire connects to it? correct me if I'm wrong.
Last edited by LT1DG; Dec 2, 2019 at 09:36 PM.
Thread Starter
Launching!
Joined: Apr 2019
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From: Bay area
Another question guys, what speed does the fans turn off? I remember driving like 25-30 mph and notice on the scanner that my fans was still on or does it stop at a higher speed? I appreciate the help coming my way guys and that fact that I got a scanner now really helps.
Thread Starter
Launching!
Joined: Apr 2019
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From: Bay area
This is the connector that goes into the ECT sensor (Engine Control Temp) sensor in the wp. Seem like the wires are kinda messed up. I wrapped it and the iac sensor (Previous photo) with electrical tape.
Thread Starter
Launching!
Joined: Apr 2019
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From: Bay area
And also I had to change out my thermostat housing for a new one because the bleeder screw on the old broke. While in the process I swapped my previous hypertech 160 thermostat with a mishimoto 160 Stat. I tested both in boiling pot both function the same, they open at the same time, but the functionality while closing was different. The hypertech closed right away once taking out the pot, but the mishimoto Stat closed at a slower paste (Which I think is good imo) Another thing I noticed is the size difference, hypertech looks shorter compare to the mishimoto. I even compare a barely use acdelco 180 Stat to the mishimoto, they both look the same. Even the crown on the top of both Stat is similar. Where the hypertech stat has different design to it. While boiling the two stats I noticed when both was open i can see the flow of water flowing thru the stats. It seem like the hypertech looked more restricted due to the design on the crown. But the mishimoto and the 180 Stat look like water was flowing thru them good due to the different straight crown.
Last edited by LT1DG; Dec 3, 2019 at 03:27 AM.
Thread Starter
Launching!
Joined: Apr 2019
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From: Bay area
You see the difference in the top part (Crown I would call it) the hypertech might be more restricted. Idk just more theory.
Look at the height differences. Mishimoto left, hypertech right
Here a Pic of mishimoto and the stock 180. Look more similar and height and size. And the crown is the same. (Sorry for the lightning)
Thread Starter
Launching!
Joined: Apr 2019
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From: Bay area
After everything was done I plugged the scanner in and fired her up. So there was some differences. My temp gauge read a little more then the pcm. (last time was the other way around) I didn't see the - 40 as it was warming up and when it hit 160 I felt the upper hose and it was kinda warm meaning the Stat was opening on time. With the hypertech though, when it got to 160 the upper hose will feel stone cold still. After letting it reach 170 I felt the hose again and it was nice and warm (But not hard) like it usually is. Probably cause I didn't drive it.
Thread Starter
Launching!
Joined: Apr 2019
Posts: 206
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From: Bay area
Gmorning guys so I got the chance to drive her earlier this morning cause I had to drop off my girlfriend to work. As I was warming it up I didn't see no - 40 even while driving it didn't pop up. But my temp is still rising slowly while cruising, when I got to my gf job the pcm sees 205, whenI hit the gas slightly 207. Occasionally it dropped back to 204-205 (Only cause I had the heater on) Then go back to 208. When I got back home it was at 219. With a 160 stat I should be at least in the 170-180 range. Its tune to, so wtheck? New wp, rebuild heads with new heads gasket, and new stats and rad cap, I'm confuse, My scanner says my fan are on while driving 30 mph. I ask this question on my past post but what speed does my fans are supposed to do to shut off? I'm hoping my fans don't stick open while moving.
Because you don't feel pressure when pressing on a hose (if it's at operating temp) then my guess is you have air in the system. Your fans are engaging, right? And they are engaging earlier than stock (I don't know what temps they are supposed to come on with Hypertech)?
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Verdad Gallardo Thread Starter
Launching!
Joined: Apr 2019
Posts: 206
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From: Bay area
Yeah no pressure in the top hose and pcm read 215. My secondary fan has already been wired by the pervious owner to stay on, the primary fans comes at 175 so they both functional. This isn't hypertech this a custom mail order tune by Solomon.
Thread Starter
Launching!
Joined: Apr 2019
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From: Bay area
Thread Starter
Launching!
Joined: Apr 2019
Posts: 206
Likes: 11
From: Bay area
How it going guys? I know I haven't got any response as of yet. But I want to keep this thread going and solve this issues. This might help others who are also having a similar problem with there lt1s. First off I remember putting bar coolent sealent in my radiator not to long ago and what remind me of it while looking into the neck of the rad, I seen some still in my coolent. I wouldnt be surprised if that's the case cause of the heating up. That why on Tuesday I'm getting the whole system flushed. Also I'm starting to think that ect sensor on the wp might be bad/defect, I know it's new but it's happens. Reason I say this is when everytime the car is warming up the temp will drop to - 40 then back to whatever it was before. There times when the temp is at 180 and of sudden it will jump to 183. I'm gonna exchange it for another one tomorrow and see how that works. When I got home tonight pcm temp said 192, I get out, touch the engine its not even hot. Another thing I notice today and this why I think the sensor is not functioning right, while watching the scanner the fans came on at different temps like fc1 came on at 182 this morning. And when I got off work it came on at 184. I thought when you tune your fans they suppose to come on at the temp you wanted. I'm confused on this part.
Teching In
Joined: Mar 2012
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You do have the restrictor plug in the water hose hose line right? It function is to reduce the water flow to the WP when the heater is off. If that restrictor piece is missing the water pump will cavitate because theses pumps both push and pull water.
Thread Starter
Launching!
Joined: Apr 2019
Posts: 206
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From: Bay area
Are you talking about the bleeder screw? If so then yes.
Thread Starter
Launching!
Joined: Apr 2019
Posts: 206
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From: Bay area
Yeah, the gasket that came with it was a lttle to thick so I swapped it with my 180 gasket. After the install I did notice my temp was at a steady 177 while cruising it even when down a bit without using the heater, But still rise up. I think I got a air pocket somewhere and I think ECT sensor is a defect just cause the readings on getting off the scanner. Or maybe it's the wire in pic that i posted with ect sensor connector.
TECH Veteran
Joined: Apr 2008
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Haven't read the whole thread but you mentioned Bars leak in radiator.....you sure the radiator is not partially clogged?...Bars leak can do that
You can ohm the temp sensor to see if it corresponds to the temp/ohm range noted on this grid
courtesy of shbox
http://shbox.com/1/4th_gen_tech2.html#ect
You can ohm the temp sensor to see if it corresponds to the temp/ohm range noted on this grid
courtesy of shbox
http://shbox.com/1/4th_gen_tech2.html#ect
Thread Starter
Launching!
Joined: Apr 2019
Posts: 206
Likes: 11
From: Bay area
Haven't read the whole thread but you mentioned Bars leak in radiator.....you sure the radiator is not partially clogged?...Bars leak can do that
You can ohm the temp sensor to see if it corresponds to the temp/ohm range noted on this grid
courtesy of shbox
http://shbox.com/1/4th_gen_tech2.html#ect
You can ohm the temp sensor to see if it corresponds to the temp/ohm range noted on this grid
courtesy of shbox
http://shbox.com/1/4th_gen_tech2.html#ect
TECH Veteran
Joined: Apr 2008
Posts: 4,985
Likes: 112
