Need Help, suggestions .........

[threepwood]

Here's what this 1992 LS400 with real 170k on it is doing now and what I have done to try and fix it.  NOTE - I have checked mutiple times and the car is not throwing any codes.  Car starts, rev's very slowly.  When reving engine accelerates very slowly. When reving to high rpms the drivers side cat becomes cherry red.  Car has no power, can not go above 15 mph.  Here's what I have done.

1 - Pulled drivers side oxygen sensor and left big gapping hole open in exhaust system.  Started car.  No change or even minor improvement.  Nothing. So I don't think exhaust is plugged.

2 - replaced both coils one at a time with known good coil. No change whatsoever.

3 - replaced MAF sensor - No change whatsoever.

4 - replaced fuel filter and fuel pump.  No change whatsoever.

5 - Finally decided to take a vacuum reading at idle - solid and steady 15 inches.  According to gauge, This indicates late timing. 

6 -  Replaced ECM with known good ECM, No change whatsoever.

7 - Checked timing at idle with timing light .  Solid 10 BTDC.

8 - removed covers from both camshafts and checked timing marks with engine at zero degrees on main pulley.  Marks are perfectly aligned.

 

I am baffled.

 

[McBrian]

Ignition issue. You are misfiring in some form and raw fuel is getting to the cat and igniting there. what do the plugs look like?

[threepwood]

So I pulled and replaced with new all 4 plugs on the drivers side.  While I was at it, I measured resistance of wires.  Coil was 5k.  Coil on other (passenger side) was 4kl.  The 4 plug wires, going front to back, were 5k,14,.15k,11k.  The odd thing is the wires 5k and 11k plugs porcelian came out black and dry.  The 2 higher resistance longer wires came out perfectly normal looking but they are fed by the passenger side distributor.   Hmmm.  Would it be worth draining the cooling system and pull the distributor caps ??

[owen 430]

i need help with a body panel thing just recently got in an accident and the 06 ls430 models are pretty hard to come by im aware of the face lift stuff but i wanted to double check if i take the fenders and bumpers off of a 02 model LS430 would i be able to exchange those peices?

[McBrian]

7 hours ago, owen 430 said:

i need help with a body panel thing just recently got in an accident and the 06 ls430 models are pretty hard to come by im aware of the face lift stuff but i wanted to double check if i take the fenders and bumpers off of a 02 model LS430 would i be able to exchange those peices?

If it's within the XX-XX year model line most body panels are interchangeable

[threepwood]

I think you have the wrong thread.  But I do have a comment for you.  My stepson backed his pickup tailgate into my trunk lid accidentally and I called my local junk yard for a replacement.  Not only did they find one, they found it in the exact color of my car.  Apparently they had access to some national junk yard database.  You might want to try them. Good hunting 🐵

[threepwood]

Pulled passenger side plugs. resistance front to back was 5,14,14,8k. Plugs that had the 14k wires this time were both black and dry and fed by the drivers side distributor, just like the other side. The 5 and 8ks were normal white but fed by the passenger side distributor. I did not have extra plugs to replace them with so I put the old plugs back in. Everything seems to point to something in that drivers side distributor.

[S COOK]

I don't see how you could have such a serious problem without a trouble code, have you tried a different Code Reader?  My first thought was an MAF sensor and second thought a VVT solenoid. That's my two cents worth.

[threepwood]

It doesn't need a code reader.  You short  TE1 to E1  on the check connector and it blinks the code on the dashboard.  To check all you have to do is pull the temperature sensor on the engine and start the car.  That does throw a code.

I should also point out that when the capacitors in the ECU went bad the car went bizerk and there were no codes.   So not having a code is nothing new for this car.

[S COOK]

Okay. I had a 1978 Seville which was special ordered with an all digital dash and Destination Computer. The mph, rpm, engine temp, OP,  voltage, all read out on the dash in orange led bars. Plus the Destination computer could be set for distance and would read out Elapsed Time, elapsed miles, average speed, average fuel consumption, estimated distance on remaining fuel,  estimated time to destination, and estimated time to arrival.  That was without any OBD connection, and DTC codes could be brought up on the dash by pushing a few buttons.  Two things I learned from the Dealer.  1. If the ECU had an internal problem, it often couldn't diagnose it, because it is the module that generates the codes.  2. Not all codes could be brought up with the built-in code reader. For example my 1998 Ford can't bring up codes from the ABS braking system but they can be retrieved with a test light and jumper wire.  I apologize for the long meandering post, I had too many cups of coffee today.  Good luck and please post the cause of the problem when you find it.

[Jeremy M.]

With the cats glowing, you have a rich condition or a severe misfire condition. I'd check fuel pressure inline before the fuel rail, and then use a hose pinch-off tool on the soft line for the fuel.

If pressure drops when the hose is pinched, you have one or more leaking fuel injectors. If it holds steady, your injectors are sealing. (If it drops only with the fuel line is NOT pinched, you have a fuel pressure regulator going bad, which would be part of the fuel pump unit inside the tank)

You could also have an ignition related issue, like mentioned earlier in the thread- pull the distributor caps to inspect the distributor rotors and the contacts inside the caps, and if they haven't been replaced recently, sparkplugs and wires should be replaced. The resistance check on sparkplug wires is not always a great test, and can sometimes show the wire to be OK when it is not (when only a portion of the wire is intact internally, it will show the proper continuity, but will not carry current). A better test in my opinion is to use an inline spark tester on each wire and check for a strong, consistent spark. 

[threepwood]

Well, I haven't finished putting it all back together yet, but I do believe (although I find it unbelieable) I have finally found the real problem.  First I pulled the drivers side distributor cap and found the rotor worn and cracked. But certainly not bad enough to explain this.  I replaced it anyway because of the cracks radiating from the screws.  Restarted car, no change.  Then I decided in bed one night to ground the high tension coils of each distributor individually and try and start the car,  To my surprise, after grounding the drivers side the car would NOT start, period.  But grounding the passenger side had no effect, car started and ran poorly just the same as if it was connected.  So I tear into the passenger side distributor and find the rotor completely disintegrated.  See pictures.  Is this a known issue?  I can only guess that the last mechanic overtightened the screws, they both cracked and the one just eventually came completely apart.  The qurestion now is how many of the timing belt covers do I really need to remove to get all the debri out ?  I'm thinking I really should remove the bottom timing belt cover as the steel top pin is still missing!