1993 SC300 Cranks won't start
05-05-18, 01:16 PM
#1
Driver School Candidate
Thread Starter
Join Date: May 2018
Location: NV
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
1993 SC300 Cranks won't start
Going to provide as much information as I can.
Friend of mine bought a 1993 SC300 with a blown head gasket and an engine out of a 1996 GS300 to swap into it. We removed the intake from the filter box to the manifold on the 96 engine and swapped over the 93 stuff onto it.
Swapped the oil pan from the SC to GS block, replaced the radiator and reverse flushed the heater core, installed new spark plugs, and used the 93 engine harness then dropped it in.
After priming the fuel system it fired up on the second attempt but sputtered and died. Third attempt gave it a little gas and it stayed running. Was idling high but after replacing a torn coupler on the intake it idled and reved great. Left it running for about 20 mins to see if it would overheat and it didn't also backed it out and back into the garage to make sure the tranny was good. It was getting late that day so we called it and left.
Next day we started working on it late in the day and it would immediately start on the first crank on every attempt but would no longer rev above 1k rpm so we tried swapping out the MAF, IACV, and TPS, from the 96 intake onto the 93 intake being used on the 96 engine with no change. Called it a day figuring it would end up being something simple.
Next morning we crank the car, it runs for about 3 second and shuts off. Crank it again and runs for half a second but would not start again after that. We checked for spark on cyl 1,2, 5, and 6 by pulling the wire out and installing an old spark plug and got great spark out of each of those, didn't remove the intake/throttle body to test 3 and 4 but figured that even with only 4 cylinders firing it should still sound like it would want to start and not just crank.
Can hear the fuel pump prime, cracked bolt on fuel rail to check for fuel and it was coming out, tried starter fluid with no change, swapped out the distributor, rotor, and cap from the 93 engine onto the 96 with no change, also swapped back the MAF, IACV, and TPS, with no change. Checked timing and its fine, checked the oil and it smells like gas start thinking the injectors are flooding the cylinders, remove spark plugs 1,2,5 and 6 no fuel is puddled on the top of the pistons so we break for lunch.
Come back reinstall the plugs to crank it and it starts for half a second and won't start again after that. Start reading around various forums and read about leaking capacitors in the ECU so I remove it and find that two have a slight leak on the bottom with no bulging on top. Leaking capacitors are 100uf 10v and 220uf 16v. I have previously repaired tvs, monitors, motherboards, and psus so I used brand new Nichicon capacitors I have on hand that were ordered from digikey.com with the same temp and uf rating but higher voltage rating with no change. Called it a day.
Today, crank car and it starts for half a second and wont after that. Seems that if its left sitting long enough it will fire up for half a second. Removed intake, throttle body, and spark plugs just waiting on battery to charge some more before doing a compression check. Reason a compression check wasn't done previously was because it came from a wrecked car that another friend vouched for as running great before the accident with the water pump and timing components being changed at 108k miles with the engine having 141k at the time of the accident. Can't find my fuel pressure tester to check fuel pressure but even if it was too low or injectors weren't spraying it should have started with starter fluid. Might have missed some other info but if anyone has some suggestions or questions please respond. Thanks for any help.
UDATE: Compression numbers aren't what we wanted to see but not bad enough to keep a car from starting, like I mentioned it would always start up instantly on the first crank once we got it running.
CYL 1: 158
CYL 2: 160
CYL 3: 140
CYL 4: 175
CYL 5: 160
CYL 6: 155
Might just try to remove all the capacitors from the ECU and replace them all to see if any of the ones that look good may be bad.
Forgot to mention that after we put everything back together and cranked it the car once again fired up for half a second but after that it just cranks once again.
Friend of mine bought a 1993 SC300 with a blown head gasket and an engine out of a 1996 GS300 to swap into it. We removed the intake from the filter box to the manifold on the 96 engine and swapped over the 93 stuff onto it.
Swapped the oil pan from the SC to GS block, replaced the radiator and reverse flushed the heater core, installed new spark plugs, and used the 93 engine harness then dropped it in.
After priming the fuel system it fired up on the second attempt but sputtered and died. Third attempt gave it a little gas and it stayed running. Was idling high but after replacing a torn coupler on the intake it idled and reved great. Left it running for about 20 mins to see if it would overheat and it didn't also backed it out and back into the garage to make sure the tranny was good. It was getting late that day so we called it and left.
Next day we started working on it late in the day and it would immediately start on the first crank on every attempt but would no longer rev above 1k rpm so we tried swapping out the MAF, IACV, and TPS, from the 96 intake onto the 93 intake being used on the 96 engine with no change. Called it a day figuring it would end up being something simple.
Next morning we crank the car, it runs for about 3 second and shuts off. Crank it again and runs for half a second but would not start again after that. We checked for spark on cyl 1,2, 5, and 6 by pulling the wire out and installing an old spark plug and got great spark out of each of those, didn't remove the intake/throttle body to test 3 and 4 but figured that even with only 4 cylinders firing it should still sound like it would want to start and not just crank.
Can hear the fuel pump prime, cracked bolt on fuel rail to check for fuel and it was coming out, tried starter fluid with no change, swapped out the distributor, rotor, and cap from the 93 engine onto the 96 with no change, also swapped back the MAF, IACV, and TPS, with no change. Checked timing and its fine, checked the oil and it smells like gas start thinking the injectors are flooding the cylinders, remove spark plugs 1,2,5 and 6 no fuel is puddled on the top of the pistons so we break for lunch.
Come back reinstall the plugs to crank it and it starts for half a second and won't start again after that. Start reading around various forums and read about leaking capacitors in the ECU so I remove it and find that two have a slight leak on the bottom with no bulging on top. Leaking capacitors are 100uf 10v and 220uf 16v. I have previously repaired tvs, monitors, motherboards, and psus so I used brand new Nichicon capacitors I have on hand that were ordered from digikey.com with the same temp and uf rating but higher voltage rating with no change. Called it a day.
Today, crank car and it starts for half a second and wont after that. Seems that if its left sitting long enough it will fire up for half a second. Removed intake, throttle body, and spark plugs just waiting on battery to charge some more before doing a compression check. Reason a compression check wasn't done previously was because it came from a wrecked car that another friend vouched for as running great before the accident with the water pump and timing components being changed at 108k miles with the engine having 141k at the time of the accident. Can't find my fuel pressure tester to check fuel pressure but even if it was too low or injectors weren't spraying it should have started with starter fluid. Might have missed some other info but if anyone has some suggestions or questions please respond. Thanks for any help.
UDATE: Compression numbers aren't what we wanted to see but not bad enough to keep a car from starting, like I mentioned it would always start up instantly on the first crank once we got it running.
CYL 1: 158
CYL 2: 160
CYL 3: 140
CYL 4: 175
CYL 5: 160
CYL 6: 155
Might just try to remove all the capacitors from the ECU and replace them all to see if any of the ones that look good may be bad.
Forgot to mention that after we put everything back together and cranked it the car once again fired up for half a second but after that it just cranks once again.
Last edited by Chead; 05-06-18 at 12:49 PM.
05-07-18, 08:55 AM
#2
first off, welcome. definitely change out all the caps in the ECU while your at it. If i remember correctly some of the 400 guys had random issues starting with bad caps. can you get it to stay on by giving it gas? any black soot coming out the exhaust or nasty smell?
05-07-18, 05:56 PM
#3
Driver School Candidate
Thread Starter
Join Date: May 2018
Location: NV
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
Been a bit busy so I haven't gotten around to removing all the caps in the ECU in order to place an order for the ones I don't have.
Thanks for the suggestion and would appreciate anyone else chiming in with ideas as to what it may be.
No black soot or nasty smell.
Last edited by Chead; 05-10-18 at 09:10 PM.
05-13-18, 08:21 PM
#4
Driver School Candidate
Thread Starter
Join Date: May 2018
Location: NV
Posts: 5
Likes: 0
Received 0 Likes
on
0 Posts
So, I've been tracing as many wires as I can back to the ECU and checking all the grounds while I wait for the caps to arrive and found that the distributor ground (G-) was broken behind the plug under tape and that the G2 pin would pull out of the plug with a slight tug so I replaced the connector with the one from the spare engine harness but once again it still just cranked and wouldn't start.
I remember having watched a video on youtube a while back on how to start a non vvti 2j outside of a car so a gave it a shot.
Well I didn't follow his instructions exactly since the engine is in the car. I left the car battery installed and used a spare battery grounded to the intake manifold and providing power to all the E10 wires he mentioned. Also I didn't cut the starter and ignition wires from the body harness figure turning the ignition switch should serve the same purpose.
So now the car will fire up for about a second after 2-4 seconds of cranking just about every single time as opposed to only half a second after it sitting for 30 mins+. Tried giving it gas and it seemed to help a barely noticeable bit and using starter fluid doesn't make it last any longer that just relying on the fuel pump.
Won't be able to work on it for a few days but next time I do I should have all the caps replaced in the ECU and I might just go ahead and cut the starter and ignition wire like the guy did in the video and see if that keeps it running.
Oh yeah, I unplugged the E10 connector from the ECU and cut the E10 connector off the spare harness to set it up more or less like in the video.
I remember having watched a video on youtube a while back on how to start a non vvti 2j outside of a car so a gave it a shot.
Well I didn't follow his instructions exactly since the engine is in the car. I left the car battery installed and used a spare battery grounded to the intake manifold and providing power to all the E10 wires he mentioned. Also I didn't cut the starter and ignition wires from the body harness figure turning the ignition switch should serve the same purpose.
So now the car will fire up for about a second after 2-4 seconds of cranking just about every single time as opposed to only half a second after it sitting for 30 mins+. Tried giving it gas and it seemed to help a barely noticeable bit and using starter fluid doesn't make it last any longer that just relying on the fuel pump.
Won't be able to work on it for a few days but next time I do I should have all the caps replaced in the ECU and I might just go ahead and cut the starter and ignition wire like the guy did in the video and see if that keeps it running.
Oh yeah, I unplugged the E10 connector from the ECU and cut the E10 connector off the spare harness to set it up more or less like in the video.
Thread
Thread Starter
Forum
Replies
Last Post