RMVR53

'cept its not a turbo...87.5 XT EA82. I also just thought, I'll need to swap back to a "regular" fuel pump correct? Bill

anyone ever been there? Would I attach it to the spider or???? OR.... shall I just make a manifold adaptor and attach a 40 or 45mm side draft where the throttle body is???!!!! Bill

many thanks to Terry at Colorado Component Rebuilders, Inc. for the use of the needed distributor. Unfortunately, my problem is still present. SO...next test is to find an EA81 distributor and swap out to a points based set up and eliminate the ECU for ignition altogether. This brings me to an important question of the board. Will it work? I guess the real question is if I switch to a points system, is the ECU going to be looking for some kind of signal from the now non-existent distributor to fire the FI? Obviously the tach won't work, but I'm really running out of ideas here... BTW...all I need to do is swap the EA82 dist drive gear to the EA81 right? Bill

Chris you should check out the thread --- EA82 looses all power ---. You just might find a similarity/solution to your situation Bill

Gary, did you fix yours? Mine is also an 87.5 XT and doing the exact same thing with one addition...the tach/timing starts to jump right as it starts to die. Mine is also a warmed-up thing. Runs great till it warms up then, my guess anyway, is that when it switches from open loop to closed loop it starts this crap. And yes, the distributor for the 87.5 is specific to the XT/non turbo ONLY. No other Ru used this unit. I finally found one at a Suby dealer - how 'bout $528 for a new distributor!!! seems the module is not available separately for this car/dizzy like it is for all other models. I installed a dizzy out of an 88 and the car runs like crap (warm or cold). Anyone know what we have to do to change dizzy to newer to go back to an earlier unit (all the way bacxk to points if I have to!!) Bill F

bump

Thanks for the reminder - this is a June 87 build so it will be a 87.5 to end of production in I believe September 87 Bill

anyone in the Denver CO area have an 87 XT(4) with a black-plug distributor that I could borrow the dist for about a 1/2 hour to trouble shoot mine? I just want to swap it in and see if my problem goes away before I have to swap the brain thanks Bill

this will serve as a bump and a continued question... I'm playing with the downdrafts and will report back on what happens. As to the dizzy, anyone swap an older unit into a later car? (2 wire or sparky into a 4 wire) Bill

ok guys, I got a WHUMA and need some direction. Since my house fire 4 months I haven't messed with the 87 XT4 so its play time again. I still have a total miss-fire when it warms up (gee...if I could just go places 2 miles away or less it'd be great) so I'm comtimplating a 2 wire dizzy or even on old points shooter to bypass the ECU. Then I can tell if thats where the bugger lies. Ideas on how to wire it? My other serious consideration is a pair of downdraft 40mm webers that I picked up for a song and I'm playing with making an intake to bolt them up to the twincam (cut the flange off a spider and weld it to the bottom of the dual intake). These, along with a 2 wire or petronix might make for an interesting XT... Anyone ever got other carbs to set up on a late car? Bill F

Yeah...I'm still working on it but I'm really loosing my motivation.... 87 XT non-turbo new- coil, cap, rotor, CAS, different distributor altogether, different TPS, different MAF, different temp sensor (what else...) When cold it starts, it runs fine...wonderful in fact. After warm-up, different story. It still starts fine, idles fine, but under accceleration it just falls on its face. almost like someone turned the key off dies. Watching the tach, if you try and hold you foot in the throttle at anything above 2000 RPM the tach will drop to zero. Take your foot out of it and it springs back up to an idle point and continues running (it does this with the tach lead at the dist. plugged in or not so we're 99.9% sure its not got anything to do with the tach). Also if you attempt to hold your foot in it for say 4 or 5 seconds it starts backfiring (out the tail pipe) and develops a nasty miss (it is also doing its drop to zero/bounce up/drop to zero/etc during this). Take you foot out altogether and it goes back to a nice smooth idle. The original job was a head gasket/valve job so yes connectors were removed/etc as needed to do this. The car was sitting with the windows up and no way for mice/etc or moisture to get to the harness under the right seat. All grounds under the hood have been cleaned at least twice..and I dont think I have missed any although with the flustration level at the current point, I may have missed something simple...but I doubt it. All connectors have been removed, sprayed with contact cleaner and re-connected. Any ideas ya'll before I shoot the thing to put it out of my misery? Bill F as a ps... I have extra TPS' out of an 88XT, 88GL turbo and 88GL10 as well as a MAF out of an XT88 if someone needs stuff...

I considered them, went back out and sprayed with contact cleaner and re-fitted. Also, as McDave suggested, I removed the yellow/white plug for the tach at the coil...no tach and still did it...and checked plug tips...but thanks for the suggestions. I guess I'll start reading the fsm to find which wires I'm looking for unless someone can point me to the culprits to check first... Bill

ok...its all gone to hell now.... as posted above, ran fine with the TPS unplugged. replaced the TPS and same problem existed. Only other thing in the TPS circuit (other then the ECU) is the coolant temp sensor. Replaced that this morning. Now it won't even idle once it warms up and spits/carrys on just after warm up just sitting here. The only other thing I can think of that has been disturbed during this whole process is the harness itself. Possibility? IF so, then what other cars can I drop this engine in as I through with it... Bill

amongst other things... while getting things removed to work on a coolant temp sensor, I wanted to check on a possible non-functioning Aux Air Valve. I noticed there is a screw/nut on it that appears to contol the opening function of the value...and the nut is nearly off the screw. Anyone know how to adjust these?...I find nothing on "adjustment" in the fsm Bill

thats the single black ground wire right?

ok...never mind the street test. You can't remove the temp sensor leads with out significant moving of parts so this will be a cold/static check (after I remove 1/2 of the intake) Bill

At this point, the TPS is the only thing not back to original...and it didn't run right with it either so its no big deal. But, I am sitting here reading the fsm MPFI diagram and I notice that the temp sensor is in the TPS circuit. So I'll swap back the original TPS, do my test drive then pull the lead off the temp sensor when it screws up and see if thats it..

As with any used part, the "new" one being bad is not out of the question. It came off an early production 88 XT so I was thinking I should be safe for a June 87 XT. While there I also pulled TPS's off an 91 Loyal/GL10 and compared it to a 88 GL and they were the same (part number/etc) to each other but were not the same as the XT. I test fitted the Loyal/GL to the XT and found while the connection is the same, the bolt up was different with the connector pointing about 30 degrees up from the XT position in the parked position. It will not bolt up to the XT in this position. I also pulled one off an 88 GL wagon turbo...similar cover but has 3 extra wires - I assume for some part of the turbo function. I have not tried it yet but assume with extra wires there is extra function but at this point I might try it. Gary/anyone know a static resistance test for a TPS switch? Bill

unplugged the MAF did the same thing once it warmed up. BUT....BUT!!! it was spittin and kickin as usual. I then stopped and unplugged the TPS switch. It ran fine...no buck/kick/miss/etc....smooth as silk. Now the odd thing is, when I swapped the MAF I also swapped the TPS so this isn't the original TPS switch. NOW what am I lookin for? Bill

its on the intake on mine...and cleaned twice just for good measure! swapped the TPS this morning - still no good. Of note: since I installed the junkyard MAF I have yet to make it around the block before it starts to spit/etc. With the old MAF I could make it around the block just light on the throttle to keep it from spitting/etc. Me thinks I'm on POSSIBLY a right track here thinking its the MAF or something in that circuit? If its not the MAF, what else is there in that curcuit to check? thanks Bill

new coil and in the course of swapping the CAS swapped the distributor as well Bill

got a MAF and a TPS out of an 88 XT today and put the MAF on before I ran out of daylight. same problem...actually felt like it was a little worse. I'll put on the TPS switch tomorrow. On the probability that the TPS is fine as well (sorry...being realistic - not pessimistic) any more ideas? Bill

other than over heating it ran fine prior to the head swap (can't really call it a rebuild as all I did was replace the head, lap the valves and new head gaskets while I was there!) . tach wire??? what tach wire??? I have a 4 wire "harness" is the only thing coming out or going to the distributor. It is a spider manifold XT (June 87 build) oh...I forgot...new coil as well....also the power transistor Bill

yeah...if I can find one to borrow I'll swap it out. I might go chase one down in the junkyards. Does it have to come of an 87 MPFI intake? no check engine light - and it passes the forced light tests in the book. no it has not run right since the rebuild. Bill

I'm so sick and tired of this.... In my on-going pursuit to find the cure for my firing problems, I have replaced half the car...ok that sounds stupid but heres where I'm at.... New: plugs, wires, cap, rotor, CAS (yes I finally bought one...and it didn't fix my problem which REALLY pisses me off) fuel and air filters (ok..I was throwing parts at it early on)... cleaning/etc: removed all ground wires and cleaned at contact; removed all connections/plugs and cleaned contacts (under the hood for both); heres where I'm at: once the car warms up, the tach will bounce wildly and 99.9% of the time while under load/acceleration will miss and literally quit. Get your foot out of the gas and tach comes back and miss-fire quits. Get it going fast enough when this happens and under deceleration everything is fine...its just under throttle. Can the TPS switch do this kind of electrical crap with the tach ? If that wasn't going on I'd be looking at the TPS for sure but right now I'm at a loss... as a precurser - this is all after a 10 month tinker rebuild to replace a cracked head...ran fine prior to teardown. thanks Bill