QuestionQUESTION: I have a used 1994 dodge grand caravan V6 engine installed into my 1989 Grand Caravan. The previous owner said it had only 48k miles when the van was wrecked. Everything matches up and plugs right in accept for the engine idle at cold startup. I can’t locate the Exhaust Gas Recirculation anywhere on this 1994 motor not for lack of looking because to too could cause my symptom. Does it have an EGR on 1994 caravan V6? If so Where?
I think that the shop that did the engine install just pulled 1994 Automatic Idle motor into the 1989 Engine Control Module, Since of course they will plug right in. I suspect the shop mistakenly miss-wired the Automatic Idle motor to my 1989 Engine Control Module. I think I need to rewire the 1994 Automatic Idle Motor so the 1989 Engine Control Module runs it correctly. (Opens and closes the idle valve correctly.) My 1994 Automatic Idle Motor continuity test confirms the motor continuity from the outer 2 pins and the inner 2 pins.
I ordered a new Automatic Idle Motor for my 1989 but its all wrong with my 1994 throttle body. Has continuity on the left 2 pins and the right 2 pins.
I do believe the 1994 Automatic Idle Motor needs to be wired up differently so the 1989 Engine Control Module can control it correctly.
Can you check the 1994 Engine Control Module to Automatic Idle Motor wiring and cross-reference it with the 1989 ECM wiring to confirm the correct wire connections? Or did they introduce the pulse motor for 1994? maybe I should Change the throttle body to 1989 parts?
ANSWER: Hi Joseph,
Which size V-6 is in the '94. Also, which engine is in the '89? I can give you are more accurate answer if I knew those facts.
Roland
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QUESTION: Both Engines are 3.0L V6 the newer engine has a build of 4439 793 & 7 date 042. My Chilton's only goes to 1991 of course with no schematics on the ECM.
ANSWER: PS I compared the pin assigments for the '89 and the '95 ecm's and they are somewhat different, paricularly in the injector control area. I am not sure what sort or wiring harness/plug issues might have occured in the transplant process, but I guess if they put all the '89 parts on the '94 engine it may still be OK. But I suspect there may be different detailed engine operating parameters for those two engines, and the '89 ecm might not be set up to ideally and properly operate a '94 engine. At least it should be questionned.
Roland
Hi Joseph,
I checked the '89 AIC wiring diagrams for the V-6 3.0L as used in the cars and it appears to be identical to that shown in the '95 manual that I have for the 3.0L as used in the vans. The continuity of windings were in both cases 2 outer/2 inner. And the pins for the AIC at the ecm were identically assigned. Now I don't have the manual for an '89 van with the 3.OL so that could be different, but I don't see why. I would be surprised that an '89 AIC would have pin 1-3/2-4 continuity. I suspect that there could be other issues of using the '89 ecm with a '94 engine, but I am not sure exactly what.
Both the '93 and '95 3.0L engines had egr's, so I would assume the '94 did as well. Look for it to be mounted in the crossover pipe that starts at the left side manifold and comes around the rear of the engine to join with the right side manifold's pipe, just beyond the joint between the two pipes. Check that the valve stem moves freely by inserting a screwdriver in the slot. However, your '89 would't be wired for an egr unless it was sold in California. So if it has an egr on it, it won't work properly without the control from the ecm. But it should be shut, not slightly ajar, or you will have trouble getting it to idle properly. Thus the need to verify that it is fully seated closed when off and idling.
Roland
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QUESTION: I got the 1989 V6 3.0L pin out of the ECM. It looks like the auto Idle speed solenoid is wired ECM pins 17, 18, 19, 20 to n2>brn,n4>yel-blk,n1>gry-red,n3> vio-blk. which corresponds to n2 and n3 connected,n1 and n4 connected inside the 1989 auto idle speed solenoid. Still don’t know which one is on or off. lol
I couldn’t find a pin out for the 1994 ECM to all its sensors yet.
It does look like I have a connection to the EGR Solenoid on pin 40 and the power from the 14 pin connector on pin4 ( ignition feed input)
Could it be under the intake manifold? I can see no extra outputs on the engine exhaust manifolds anywhere but there is one vacuum going into the gap near the fuel injectors. I am going to follow pin 40 and see where it goes next. LOL
Thanks for all the help. I really enjoy bouncing ideas off of you. Joseph
AnswerPS I don't understand fully which year's controller you are using and also, which ever one you use, you have to match the harness year to the ecm because they are different. And so too will be the far end connections to the engine parts for several pins. I can't recommend which way to go, but the wiring can't be a mix of the '89 with the '94 unless if you are using the '89 ecm, then only use the mechanicals of the '94, to the exclusion of any harness to sensor/actuators of the '94. I can xerox and mail you the ecm pin-outs and diagrams that I have described to be in my possession.
Joseph,
Those ecm pins are for the '89 2.5 4 cyl. The ones for the 3.0L are 39/59, 40/60 for N1/N3, N2/N4. These are for the FWD cars, but I can't believe the ecm's are different for the vans. The N #'s are also differently assigned between the 2.5 and the 3.0, but in both cases the inner and outer two are paired at the plug of the 3.0, but the 2.5 uses a 6 pin plug. I don't find the 40=egr in the '95 diagrams for the 3.0 but rather 35. 40 is shown for the 2.5L=egr solenoid on the California engine in '89.
Just follow the pipe from the front exhaust manifold I if there is one that indeed goes under the intake/throttle body area. If there is no such pipe then there is no egr on your exhaust system (if the exhaust is from the '89 van it won't have an egr if the exhaust manifold on the '94 engine is in use then there should be a pipe on it).
Roland
