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1998 3.8 wont start/misfire after rad install, help?

W

westjohn

New member
hello all, im new to the forums but have a pretty big issue, Thursday night my girlfriend was driving her 1998 grand prix with the n/a 3.8 when the tank on the rad busted, so Saturday morning I went and picked it up with my car trailer and brought it back to my place, take note that the car ran and drove onto the trailer, and then ran and drove off the trailer, all while running great, I disconnected the battery and removed it (couldn't get the rad out without removing it) removed the fans, , motor mounts, everything necessary to remove the rad. replaced the radiator, reinstalled everything, reinstalled the battery, and it wouldn't crank for the life of me, after a good solid 30 seconds of cranking it fired up, but idled at about 1700 rpms, after about another 30 second, it started misfiring, upon further investigation it seems I had pulled two spark plug boots loose, install two new wires (the ones that were on it were a month old) still having the same issue, the codes its giving me are

P0101 MAF sensor
P0118 Temp sensor
P0123 tps out of range
P0403 EGR flow circuit,

with these codes the car runs at 1700 rpms at idle, but runs fine, no stumbling, misfiring or anything then it throws this code which has me confused

P1635 manufacture controller malfunction

the only wiring harness I could have potentially damaged is the power fuse/relay box near the battery going to ECM, ive checked all the connections and it doesn't appear to be loose, ive checked all fuses, connectors, anything I can think of, could any point me in the right directions here??? she needs her car for tomorrow, and I cant for the life of me figure out what ive pulled loose or broke
 


checked all fuses, it was empty of all coolant when I pulled it into my garage and was running great, im just curious on the P1635 code, I googled it and never got an answer
 
my little autozone scanner said it was a manufacture controlled malfunction, im starting to wonder if she popped a head because it wont hold any pressure in the cooling system
 


Well, I just gave you the exact definition of what it is. Popping a head on these cars is pretty uncommon. Also, it won't cause any of the codes you're getting. These sensors all lie in a small harness that goes to the throttle body. Some of them share a fuse too...the one for the EGR IIRC. That's why I sent you in that direction. Did the coolant tank blow on the D/S or P/S? If it blew on the D/S maybe it got some coolant somehow in the ECM connector. I'd still quadruple check all those fuses (including the ones in the car) just to be safe. If on the P/S, the ECM power connectors are under that fuse box and may be filled with coolant.
 
the tank on the driver side blew, sending coolant all over the air box, Ill try undoing the ECM connector and seeing if any water comes out, im draining the water I put in the rad for leak checking to see if maybe im getting water on a spark plug, it still wouldn't explain why its misfiring when t throws the code though. but worth a shot, almost did a reset by touching the negative and positive leads together and doing a hard reset on everything
 
if its not holding air pressure you'd see a leak. check all hoses, the 2 plastic elbows, and heater hoses too.

check the oil for coolant, or it being over full now.

if thats all dry, pull the pass side carpet up and see if the floor is wet, if so the heater core failed and is leaking.
 
heater core has been bypassed, ive chcked all over for leaks and im not seeing anything but the oil is not milky or over full, now when go to crank it over will it only crank every now and then
 


checked ECM connections, all were good and coolant free as well, checked all fuses, their good as well, car will not start now what so ever, its hit or miss on weather it cranks over or not as well, im clueless guys
 
I pulled the plugs, their burnt black to a crisp, car has spark, but will not run even off starter fluid, can I get some more suggestions? the way it turns over I feel it has a dead cylinder
 
is it getting fuel? push the pin in the valve on the fuel rail, under the fat black cap.

watch your eyes, if its got pressure its gonna spray.
 
getting fuel pressure, getting spark, will not fire even on starting fluid, sounds like it has a dead cylinder, about to go pull the plugs out of the rear bank
 
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