i have 1992 mercedes 400e 5.0 eng, auto trans, 160,000 miles, the abs light is on, after it warms up, it goes into like a limp mode where the rpm wont go over 1,000. i was wondering if it had obd 2 and if it does where the port to hook up is? or any other suggestions.

No obd2, you need a factory type scan tool with the 38 pin connector or you may need the pulse counter connected to the 16 pin data connetor under hood.

Check the wiring harness on the throttle body-cut open the plastic that covers the wires( it looks like a large cable) , more than likley the insolation on the wires is gone. the only repair is a new throttle body $$$$$ 1,300.00 or so.

thanks, i did get the abs light to go out, i ohmed all the sensors at the wheels they were good, i pulled the cover off the big aluminum casting where the computer is and there were 4 10amp fuses, 1 was blown, it fixed the cruise control and the abs light, but it is still going into a limp mode when the car is driven about 15 miles, i will check the throttle body, thanks again. mike

if you are blowing fuses in the base module, what fuse was it? Check the rest of the wiring on the engine, if the insolation is falling off, you need a harness.

i checked the engine harnes going from the computer at firewall to the engine, it is bad, all the plastic is gone off the organic wiring harness, thanks for your input everyone, i got a new harness coming, i think its a good price for an oem harness $585 delivered, so everyone pull the long black covers running down the top of the engine about 5 inches to the passenger side of the throttle body the harness goes to just about every sensor on the engine it looks like, i will let you know if it fixes my problems in a week or so.
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okay, i got a new engine wiring harnes installed, still had the problem, engine goes into a limp mode after being driven about 10 miles and reaching operating temp, i also changed the ignition module with no help.

did you cut open the harness that is part of the throttle body? it has the same type of wiring that the engine harness had. do you have access to a factory type scan tool that can test out the throttle body control unit for fault codes? That is a sure way to help in finding out why it is going into limp mode.

okay, i got the main problem solved with your help, thank you so much, i replaced the throttle body and harness, this solved the engine going into limp mode or not reving over 1,000 rpm after it reached operating temp. i did cut open the old throt body harness and the wires looked okay, i took it apart and could not find any obvious defects, but it was the problem, i only have a few more items to fix,

1 problem i been having is, the airconditioner, it works great, while driven, when the car shifts, which it is automatic, if the engine is reved up over 2,000 rpm, right when it shifts the compressor kicks out and does not reengage for a few minutes, if the car is babyed letting off the gas to shift the compressor will stay engaged, the problem is intermitent but pretty regular problem, and ideas??

If i remember correctly there is a speed sensor on the compressor. Check the belt, if it is loose your compressor could slip. the compressor relay or computer will then shut off the compressor.

another check, at the a/c pressure switch red/blue wires, engine running a/c off-backprobe the wiring there should be about 12 volts. Turn on the a/c and the voltage needs to drop to about 1 volt. This is the command to turn the compressor on from the climate control head.

The relay for the ac compressor could be faulty.
There is a procedure though for checking all the inputs and out puts for this relay. They all need checked before you just put a relay in it though.
There is a input for engine temp, engine speed, freon pressure, etc. ( the belt slipping could very well be the culprit because it is the most common)
I will try to find the list of things to check and which wires to check. I will try to get this posted for you.

i changed the belt and that helped alot, now occasionally when i start the car in the morning after sitting all night, the a/c compressor will not kick in until the engine has reached operating temp, and engine shut off and restarted, then the a/c works great the rest of the day, anyway i haven't got to do all the checks in the above 2 post that you guys left for me so i will check those out, thanks mike