Hello, I have a 1996 e300d. I got a 0220 code (acc. throttle position circuit b malfunction) it puts car into limp mode only when the car moves. otherwise, I can sit in Park and rev the motor all day. as soon as I put into drive and start to roll it throws code and I loose throttle. Here is what I've already done: 1) unraveled wire harness because im aware of biodegradable wire- no breaking insulation and no wire grounding to ground except brown wire(ground wire) from TPS. Im getting full conductivity from each of 8 wires to ECM. 2) I bought new TPS ($500) 3) new MAP sensor ($120) and replaced vacuum line and checked its wire. 4) cleaned intake and EGR body and checked operation of intake resonance valves. 5) replaced MAF ($30) and checked wires. 6) checked cross over is functioning and replaced vacuum hoses. 7) replaced crankshaft position sensor and new cable.($65) 8) replaced k40 relay box ($140). 9) adjusted TPS Bowden cable to foot throttle lever and Bowden to tranny per manufactures specs...... I'm lost !!! like I said , I can sit in park and rev motor with no codes coming on- when I put car into drive it begins to roll and goes into limp mode - sometimes immediately and sometimes a 1/4 mile up road ... Please help , I am demoralized

I'll buy a catcher's mitt and get downwind of you!

But seriously, it's WAY too new for me. Hope the guys have some info - and good luck on this.

Dan

Sounds like a transmission issue. Maybe Low fluid for starters.

Have any codes pulled?

96 is such an oddball year because of the electronic throttle and injection pump connected to the purely hydraulic 722.4.

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CENSORED due to not family friendly words

Don't know if this will work with your vehicle, but you have nothing to lose, and it doesn't cost a penny to try:



A search on "throttle body reset":

Quote:
1. Get in your car, it doesn't matter if you close the door or not.

2. Turn the key to the on (not start) position, the position just before the starter turns over.

3. Press the gas pedal to the floor with the key in the "on" position.

4. Hold the pedal to the floor for five seconds, then turn the key back to the "off" position (don't remove the key), then release the gas pedal.

5. Wait 2 mins for a full alignment.

6. Drive the car as you always do.

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96 E300d

This is a puzzler.

Question: Being very granular here, but does it go into limp mode ONLY once the wheels are actually moving, or can it go (even sometimes) into limp mode when Drive is engaged, but you haven't rolled at all?

This is off the wall, primarily because the P0020 code is so specific to the throttle circuit, but somehow I'm thinking of a faulty signal originating from the tranny's gear selector position sensor. (Being it's the older 4-speed trans, and not the 5-speed) If it ONLY happens once the wheels turn, then the wheel's speed sensors come into play... and what could they do to send a signal that causes the CPU to throw the anchor overboard?

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Current rolling stock:
2001 E55 183,000+ Newest member of the fleet.
2002 E320 83,000 - The "cream-puff"!
1992 500E 217,000+
1995 E300D 412,000+
1998 E300D 155,000+
2001 E320 227,000+
2001 E320 Wagon, 177,000+

Prior MBZ’s:
1952 220 Cab A
1966 300SE
1971 280SE
1973 350SLC (euro)
1980 450SLC
1980 450SLC (#2)
1978 450SLC 5.0
1984 300D ~243,000 & fondly remembered
1993 500E - sorely missed.
1975 VW Scirocco w/ slightly de-tuned Super-Vee engine - Sold after 30+ years.

You need the exact _full_ MB code description, RE: Circuit high , circuit low , shorted to power , shorted to ground. There also will be a very specific MB troubleshooting procedure to follow.

Your attempt started out sort of on track ( except not for knowing the exact code description ) but then diverges into wild random guessing.

Hang a scope / volt meter on the B ckt signal and look for a clean signal. These systems rely on two input circuits with the computer monitoring both. The signal from A and B won't be the same, this is to prevent jumpering one circuit to the other in an attempt to patch things up.

I have nothing helpful to your problem other than VERIFYING you have all ground circuits in the car replaced, and if your car has an aux battery, that it is good.

But if you want to throw money, I'm good to catch some!

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!