Jump to content


90 Ls400 Shows Code 13


dave_m8
 Share

Recommended Posts

My daughter has a 90 LS400 with 170K miles on it, the car suddenly developed a low RPM misfire & the CEL light came on.

I pulled the code & it reads 13, which is " RPM signal no. 2 " (Not much help)

I checked all the plugs & wires, all the plugs seem to be firing & the leads resistance is in the 5-14KOhm

range, including the coil leads. I also checked the compression since I had the plugs out, drivers side cylinders all showed

170psi, the passenger side showed 145-155psi ?

Could something like the timing belt jumping on the passenger side cam wheel cause something like this ?

Anybody had a CEL code 13 diagnosed?

Link to comment
Share on other sites

My daughter has a 90 LS400 with 170K miles on it, the car suddenly developed a low RPM misfire & the CEL light came on.

I pulled the code & it reads 13, which is " RPM signal no. 2 " (Not much help)

I checked all the plugs & wires, all the plugs seem to be firing & the leads resistance is in the 5-14KOhm

range, including the coil leads. I also checked the compression since I had the plugs out, drivers side cylinders all showed

170psi, the passenger side showed 145-155psi ?

Could something like the timing belt jumping on the passenger side cam wheel cause something like this ?

Anybody had a CEL code 13 diagnosed?

Looks like the problem was caused by the timing belt jumping a tooth on one cam. Replaced the timing belt (& water pump

while I was in there) and the engine runs great again - all cylinders show 170+ psi compression.

Great tutorial on changing the belt/water pump here

http://www.lexls.com/tutorials/engine/timingbelt.html#20

rgds Dave

Link to comment
Share on other sites

Here are some pages form the repair manual for "check engine" light problems:

Here's some extra info: MOMENTARY INTERRUPTION

During diagnosis, if Codes 13, 22, 24, 41 or 47 are stored in

ECU memory and no trouble can be found with these circuits, it will be

necessary to perform a momentary interruption test.

1) Clear codes from ECU memory. See CLEARING CODES in this

article. With ignition off, connect a jumper wire between terminals E1

and TE1 of TDCL connector.

2) Start engine. Ensure CHECK engine light goes out. Pull

lightly on wires and apply vibration to connectors and relays

associated with diagnostic codes.

3) During this test if CHECK engine light illuminates, it

indicates which connector or where in the wire harness there is a

fault. Repair as necessary.

4) Clear diagnostic codes. Start engine. If CHECK engine

light does not go out, check thoroughly for faulty connections.

Perform MOMENTARY INTERRUPTION LS400 test again. If CHECK engine light

still will not go out, see LS400 CONTROL UNIT in I - SYSTEM/COMP TESTS

article.

sorry cant upload the info for code 13 but i will find a way to get it on here

Link to comment
Share on other sites

My daughter has a 90 LS400 with 170K miles on it, the car suddenly developed a low RPM misfire & the CEL light came on.

I pulled the code & it reads 13, which is " RPM signal no. 2 " (Not much help)

I checked all the plugs & wires, all the plugs seem to be firing & the leads resistance is in the 5-14KOhm

range, including the coil leads. I also checked the compression since I had the plugs out, drivers side cylinders all showed

170psi, the passenger side showed 145-155psi ?

Could something like the timing belt jumping on the passenger side cam wheel cause something like this ?

Anybody had a CEL code 13 diagnosed?

Looks like the problem was caused by the timing belt jumping a tooth on one cam. Replaced the timing belt (& water pump

while I was in there) and the engine runs great again - all cylinders show 170+ psi compression.

Great tutorial on changing the belt/water pump here

http://www.lexls.com/tutorials/engine/timingbelt.html#20

rgds Dave

Glad you figured it out, a belt jumping a tooth on a cam cog almost defies logic as the belt is in contact with over 1/2 of the teeth on the cog, but I do believe you. Motors can do weird thinks. I broke a cam in half on a 1.5l Honda motor, cam bearing in the head seized and just twisted it right in half.

Link to comment
Share on other sites

  • 4 years later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share



×
×
  • Create New...

Forums


News


Membership