several problems LT1

[yellowVette]

hello this is my first time using this forum...wealth of info

i have a 1996 LT1, great car still hauls, and to quote from True Lies "the vette gets em wet"

well lately i have been having several probs, and i cant find any kind of solution to them...
ill start off with eng. probs : 1) sometimes when cruising(at night and coolant temp is pretty high but oil temp is low) when getting on the pedal, i hear a knocking sound, kind of like a lifter or valve sound hitting..this happens only once in a while.. i have talked to several ppl and they say its not a valve or lifter, but say it may be an O2 sensor....i have never heard of anyone having this problem so i wouldnt know where to start :confused
2) the temp of the engine... this is wierd to me cuz i can cruise a long time, and only the coolant temp gets pretty high, and the oil temp doesnt... id suspect the thermostat, but wouldnt it cause the oil to get hot as well? easy to change the thermostat but maybe something else can be causing this as well..

prob with the transmission : this is bothering me alot.... i have an auto tranny... when i shift down to 1, and gun it hard, the RPMs go up normally then all of a sudden it bogs down nasty, then when i shift up to 2, it'll catch and goes as normal....again this only happens sometimes not always(i DO have the traction control OFF)....ppl say thats not a sign of a slipping tranny, but may be electrical? i have no idea

oh and also the climate control for the AC... i have the same prob as most other ppl do...i do have to keep it on 60 so it can always be blowing cold air...the temp display always moves around and it will even go down to -30 degrees when its 90 outside and it'll start blowing hot air! sometimes the buttons dont work right, they dim then go to normal, then i windup opening the windows..want some help with this also

well thanx for any help !

 

[charley88]

What are the coolant and oil temp readings? I've noticed my oil temp can lag behind my coolant temp for about 15 min.

As for the O2 sensor, what are the codes your ECM are giving you?

 

[Vettelt193]

Please post numbers, temperature oil and coolant, mileage of the car...

most stock LT1's came with 195 degree thermostats... this means a little over 200 on the highway is normal temp

Tranny, what RPM does it do it at? I suspect you are hitting red-line... Automatics are automatic, it is better to let the tranny do the work...

 

[yellowVette]

the tranny will do it @ 3500 to about 4000... i have hit red line before on 1 and i know i havent hit red line when i have gunned it...more or less in the middle RPM range, but i have noticed it(when i actually did look) in that range...

i havent driven the vette in a few days, so i just got these off the panel of where the markers usually are : the oil temp is pretty normal, usually on the 1st notch after 215, almost never goes up nore then that during cruising....
the temp goes pretty high, its on the 3rd notch after 185...or the one above the 260 mark, its usually right in there.....almost goes to the 260 mark but then gets cooled off somewhat

so thats pretty much the probs i have... and the one with the AC heheh..

76,541k miles on a 1995 LT1

 

[Vettelt193]

The analog guages aren't the best... They are much better on my '96 than they were on my '93... I don't think my Dad's '91 oil temp guage even worked, because it hardly moved at all.... Hit the 'Guages' button next time you are in the car, and scroll through the digital read outs... On the highway, you should be a bit over 200 degrees for the coolant temp. I would highly advise getting a 160 degree thermostat, It has helped many vette owners keep the temperatures down a bit... With the A/C on, the fans run to keep the car cool, with it off, the car will get up to 230 before the fans kick on, and should turn off about 215

-The tranny problem may not be the tranny at all... could it be the engine? It sounds like a fuel problem, cutting off... even a low gas problem... I am not too sure here... does it happen when the car is shifting itself? I am wondering if the computer gets confused, and starts to cut out fuel? I am just throwing ideas around to see what others have to say as well.

-The AC could be the sensor, or the connection to the unit, or the unit itself... I have not experienced problems with this part of my vette(s) so I can't help too much.

 

[96Holly]

First of all welcome to the club!!!

My 2 cents is...

I am not sure were the sensors are for the temp but if you have an air bubble in the system couldn't this effect the water temp but not the oil? Again I am not sure if this could happen but I do know you have to do an air bleed to the coolent system to remove air bubbles.

I am learning Vette maintinance with everyone else...

 

[vigman]

More questions

"when getting on the pedal, i hear a knocking sound, kind of like a lifter or valve sound hitting..this happens only once in a while.."

Sounds like pinging to me...does it happen when the car is cold?

"only the coolant temp gets pretty high, and the oil temp doesnt."

When was the last time the cooling system was flushed?

And without some fan/chip mods..she will ALWAYS run HOT!


" I have an auto tranny... when i shift down to 1, and gun it hard, the RPMs go up normally then all of a sudden it bogs down nasty,"


If its BOGGIN' I think its not the tranny.. but a fuel..or opti spark problem..invert the test

If you hold the RPM that you downshifted to
( eg 4000rpm ) by locking the car in 1st.... does it bog now?

I'll get back to you on the AC errors


Vig!

 

[vigman]

A/C trouble codes

A/C Diagnostic Trouble codes

When the A/C controller head thinks it has a problem... start the car & watch closely...

The MODE button you have depressed
(E.G. AUTO) will flash for one minute then go out...

The A/C controller it CRYING HHHEEEELLLLPPPPPP!


Hold the arrow up & the arrow down buttons for 5 seconds the display will show 00
( to let you know your in )
Hit the Auto button
and is should scroll through the code(s) that you have

00= No problem
01= temp door motor goof
02= temp door motor goof (different problem )
03= ambient sensor OPENED UP/disconnected
04= ambient sensor Shorted out/ kaboom
05= internal sensor OPENED
06= internal sensor Shorted out/ kaboom
07= Solar sensor ( in dash ) open
09= Low gas
10= CPU has blow it's mind

After this is done...by pressing the up & down arrows you can pole the different circuts and when you find the one you are looking for
Press AUTO and it will tell you what it thinks it sees. ( number value )

To get out of Diag's

Hit defrost..( or any other AC control)


Try this.....

Vig!