2.3 runs well cold then goes to hell

[chachi]

just cannot figure this one out. 2.3 RJE engine in a '91 auto. van has trouble starting cold and but will catch and start if you give it a little gas. then runs ok at first, just a little slow to respond to throttle. ran it around the block today on this warm sunny day and in the first five minutes it was running great. held its idle fine in traffic and responded well to throttle.

then after 7 minutes or so, when you're at cruising speed and you go to round a corner, slowing down but then simultaneously giving it a little gas for the turn, your throttle will make it want to die. backing off the throttle and just feathering the gas will sometimes let you drive for awhile, but eventually any throttle is too much and it will die at any press of the gas pedal. starting the van after that (even in the middle of an intersection) is fruitless. if the van is left to sit over night (or just until it cools down..?) it will start again fine as per above.

van maintains good fuel pressure through this whole series. new O2 sensor, if this is unplugged while it's having one of these fits it will REALLY not start. rebuilt injectors in the last 200 miles.

the behavior is as if the fuel enrichment is not enough at first, and then progressively too much, like it's not reading the actual engine conditions. at one time i swapped out the ECU and it didn't change my immediate problems but that was so many problems ago i would certainly be willing to try it again if that's what this looks like.

thanks for your ideas!
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'74 transporter panel
'91 vanagon carat NAHT

[raoul mitgong]

t2 sensor?

http://www.van-cafe.com/coolant-temp.-sensor-w-o-ring

-d
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84 Westy with a 2.1 (Groover)
86 Tintop Syncro (Crow)
86 Tintop Syncro to Westy project (Tom Servo)
91 Westy (Only the top 12 inches of this van (a burn victim))

[chachi]

[raoul mitgong]

You could check the resistance per the Bentley prior to startup and after it gets hot and starts to act up. Check it at the pins at the ECU connector (I think that is where the Bentley has you check them) to make sure the wires aren't the culprit.
-d
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84 Westy with a 2.1 (Groover)
86 Tintop Syncro (Crow)
86 Tintop Syncro to Westy project (Tom Servo)
91 Westy (Only the top 12 inches of this van (a burn victim))

[jberger]

I helped out a fellow Sambaist a few years ago with an automatic and an RJE 2.3. It really ran poorly, stumbling and dying if you gave it gas to pull away from a stop. In that van it was all down to tuning. Here is the list.. not necessarily in that order.

1. Idle switch
2. AFM adjustment
3. Timing
4. Valve adjustment

[chachi]

[jberger]

[0to60in6min]

https://www.thesamba.com/vw/forum/viewtopic.php?t=356377

[mtnride1]

I have a GW 2.3 it would run fine and start quick than after driving it would take two cranks to start. Driving back from AZ last year it did kind of what you are talking about than it finally just died. It ended up being the throttle positioning switch. took it to a shop in Prescott (good guy) I think it was called Air cooled only but Chris knows h2o cooled really well. Got it all dialed in and came home with no more problems. Good Luck.
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87 westy 2wd (NED)

[chachi]

[edited for clarity, see below]
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'74 transporter panel
'91 vanagon carat NAHT

[chachi]

went back in with a better meter and confirmed old temp 2 sensor and harness were working close to spec, at least at ambient temps. i went through the tests on 24.61 and 24.62 and the one standout was that when i jumpered 3+13 the fuel pump did not run audibly. i do have pressure on the rail but possibly the ECU is not passing that fuel around?

checked the TPS and it seems ok. i adjusted it closer than it was, didn’t help me start the van so don’t know if it helped. i’m gonna order a new one anyway.
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'74 transporter panel
'91 vanagon carat NAHT

[t3 kopf]

The ECU does not use the Temp 2 for reference when the engine is warmed up, it uses the 02 sensor then. I think you have an AFM problem.
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'90 Carat w/ '95 phase 1 EJ22 OBD2 conversion