My buddy just recently purchased a 93 lt1 formula automatic, bone stock except for an intake, it has 125,000 miles on it. Car runs and drives around town fine but for some reason it seems to bog and is definatley way underpowered. My crappy rav 4 can smoke it. When you drive off normal (from a stop) it seems to work great and goes through all the gears shifts fine (4000 shift points when you slam on it in drive, is this stock?). But if your already moving and decide to take a turn it seems like it shifts up a gear and bogs really bad until you step on it more than 50% and it will jump rpms and be fine again. The check engine light comes on for a second but very rarely.

Possible missfire somewhere????????
Trans in some kind of limp mode?????


We just changed the sprak plugs/battery/oil and filter about to do a trans flush tomorrow.

Help is much appreciated we really need to get this thing running for him. Thanks for the help everyone!

 

Check the codes? On a '93 I believe you can use a jumper wire on the data port to flash the SES light for the appropriate code(s). Sounds like either fuel or ignition. Possibly 02's are bad as well.

 

Just found a place for the codes thanks that was a great idea i didnt know you could do that. I will be doing the fuel filter tomorrow also since there cheap. If that stuff doesnt work then I will check out the o2's. Thanks again for the help.

 

A great site for info on 4th gens
http://shbox.com/page/index.html

What you need
http://shbox.com/1/dlc2.jpg

And what they mean
https://ls1tech.com/forums/lt1-lt4-m...eshooting.html

 

yeah with a 93 you can take a paperclip and jumper the top right pin and the one next to it and the cel will flash the codes

 

Check the fuel pressure too with the vacuum off the fuel pressure regulator. It should be between 43 and 45psi (43.5psi to be exact).

 

Awesome thanks guys, I will check the Fuel pressure also. You literally have to floor this thing to get it going.... I will let ya guys know what happens tonight or tomorrow morning at the latest.

 

Got around to checking the codes today these are what came up.

code 26 quad-driver module (computer) circuit #1 fault

code 69 for air conditioning or something.

Any ideas as to if these may be part of the problem?


Also my buddy swares it only bogs when it goes into 3rd gear but it is also still underpowered we will be doing the fuel filter and pressure check tomorrow.


Thanks for the help again everyone!

 

Disconnect the battery for 1 minute and clear the codes and then see what happens. If the problem still exists then read the codes.

 

Sounds about right for a stock LT1. Id put an LS in it.







JK, In reality you may want to do a compression check if the fuel pressure checks out ok.

 

If fuel pressure checks out I have a feeling the plugs and wires need to be changed.

Here's some reading on Code 26.

http://www.saturnfans.com/forums/arc...php/t-284.html

 

26 evap cannister purge solenoid circut
69 a/c clutch circut

 

Because it's a "quad driver" code it doesn't necessarily mean it's just one component going bad. The quad driver monitors signals from four different devices. All those devices need to be checked. Just need to pinpoint which devices are on that driver.

 

Just realized yesterday that the kickdown cable for the trans is shot. We decided to try and adjust it thinking this could be the issue and it would not adjust it will only stay super loose. Thinking this has alot to do with it! Anyone know where to get one?? There discountinued obviously. Thanks again guys. Also that evap code makes alot of sense since the gas tank will only fill up if you do it REALLY REALLY slow so im workin on deleting that and venting it better for him later today.

 

You may try the local junk- salvage yards for the cable. Any '92-'93 lt1 Camaro or Vette, possibly the tunedport cars since the throttle body was about the same and they ran the 700r.

 

If its still running like **** listen for a dead mis if you know how that sounds. Might be a roasted plug wire

 

we did the gas tank evap and that didnt seem to help with the gas tank. I havent replaced the wires yet but i think there was one that was burnt now that i think about it. It also over heated the other day so i replaced the water pump and thermostat. I REALLY need this back on the road ASAPso if anyone else has some ideas then PLEASE let me or Keith know ASAP!