bad hesitation on my new mkII

SolidStateS15 · 09-18-2006, 05:39 PM

i just picked up an 85 mkII and am trying to get the lil old 5m going again till i get the 7mgt swap done. it's acting very weird, and when i got it the person said it was a clogged cat. it is acting something like that, where it just has no power and when you even sit at idle and floor the pedal it does nothing for like 10 sec then finally the rpm's will start to climb slowly but still not gain much. i pulled the cat and that didn't help, and it didn't look that bad. i also changed the spark plugs which were in horrible shape, but still didn't help. my next things are fuel filter, check for vac leaks, and check some other ignition stuff. i'll do a compression test, but i don't think it's the HG since there aren't other signs of it. i did pull the intake apart and made sure it was all tight and put on a new cone filter. the last owner has already installed a new coil and plug wires, tps, cap&rotor, and a few other things. i was thinking the tps could possibly be off and may need alignment. not sure what else to look for since i am new to these engines. could a bad clutch cause this? cause the clutch does seem pretty weak, it's probably original and there's 165k on the it now. not sure what would affect the rpm's like this.

midwestmk2 · 09-18-2006, 05:49 PM

I would say since he replaced the TPS then he just put it on with out adjusting it..Check it out then i would say check the timing also..

SolidStateS15 · 09-18-2006, 06:04 PM

Quote:

Originally Posted by midwestmk2

I would say since he replaced the TPS then he just put it on with out adjusting it..Check it out then i would say check the timing also..

yeah what i was thinking too, and it also looks like the timing belt was replaced not too long ago as well so it should be fine but i can check. is there a voltage chart in the shop manual for adjusting the tps? also can i check the timing with a light, or is it more complicated like some other engines that are electronically controlled.

midwestmk2 · 09-18-2006, 08:35 PM

Your best bet is to turn the crank to TDC and make sure the timing marks for the cams are alighned properly..You can then adjust thetiming with a light and the distributor..On the tps though i just moved mine little by little until i was satisfied..

SolidStateS15 · 09-18-2006, 09:49 PM

i think i found the problem. the timing is really bad, umm the crank pully bolt wasn't even tight at all so it's been spinning on it's own and throwing off the timing. so now i just need to strip it all down and set it right. just sux on this thing because there is too much crap in the way so u have to remove it all. gonna take longer to remove all the belts and fan then to set the timing itself

. i just hope there are no bent valves, is this an interference engine? that could also explain the loud tapping when the engine did run, i though it was just the HLA's but it could be valves.

midwestmk2 · 09-18-2006, 11:25 PM

I dont know for sure or not if it is a interference engine or not but i dont think so..If the crank pulley is turning then your going to need a new crank keyway..Hoprfully the keyway slot isnt to hurt or youll be getting yourself a new crank..You can weld them in but it isnt recomended..

SolidStateS15 · 09-19-2006, 12:48 AM

Quote:

Originally Posted by midwestmk2

I dont know for sure or not if it is a interference engine or not but i dont think so..If the crank pulley is turning then your going to need a new crank keyway..Hoprfully the keyway slot isnt to hurt or youll be getting yourself a new crank..You can weld them in but it isnt recomended..

i sure hope not or this engine is toast. if the crank is stripped then i'm done i guess till the swap. i just hope that it's fine and just needs to be tightened or possibly a key.

midwestmk2 · 09-19-2006, 01:16 AM

Keep me posted on your progress if any..

supra1985turbo · 09-22-2006, 05:56 PM

The 5m engine is not an interferance engine. I have a 85 5m and when I first rebuilt the engine I did not want to be going down the 1/4 mile strip and the cam belt brake and mess up the engine. So when I was to that point of lining every thing up I just stuck the belt on and hand turned the engine over about 20 times never hit a valve.

SolidStateS15 · 09-23-2006, 12:33 AM

thanks for the info. i actually got it running today which was great. i just had to keep messing with the timing because it would not hold it. i would set it and spin a few times and it would be off again?? not sure what the deal was but it took about 4 times before it would stay together. i got it all back together and took it out for a test run and it was perfect. first time i have actually gotten to drive in it so it felt good.

09-18-2006, 05:39 PM	#1
SolidStateS15 Stock Join Date: Sep 2006 Location: SE Maryland Posts: 16	bad hesitation on my new mkII i just picked up an 85 mkII and am trying to get the lil old 5m going again till i get the 7mgt swap done. it's acting very weird, and when i got it the person said it was a clogged cat. it is acting something like that, where it just has no power and when you even sit at idle and floor the pedal it does nothing for like 10 sec then finally the rpm's will start to climb slowly but still not gain much. i pulled the cat and that didn't help, and it didn't look that bad. i also changed the spark plugs which were in horrible shape, but still didn't help. my next things are fuel filter, check for vac leaks, and check some other ignition stuff. i'll do a compression test, but i don't think it's the HG since there aren't other signs of it. i did pull the intake apart and made sure it was all tight and put on a new cone filter. the last owner has already installed a new coil and plug wires, tps, cap&rotor, and a few other things. i was thinking the tps could possibly be off and may need alignment. not sure what else to look for since i am new to these engines. could a bad clutch cause this? cause the clutch does seem pretty weak, it's probably original and there's 165k on the it now. not sure what would affect the rpm's like this. Last edited by SolidStateS15; 09-18-2006 at 05:42 PM.

09-18-2006, 05:49 PM	#2
midwestmk2 3" Exhaust Join Date: May 2005 Location: STL ,MO. Posts: 206	I would say since he replaced the TPS then he just put it on with out adjusting it..Check it out then i would say check the timing also.. __________________ 83 p-type,5spd,4;10 gears,New 86 cressida 5MGE 195hp,HKS metal head gasket,Cressida injectors,d-port intake runners,No EGR,No cat,Tweaked MAF,Custom cold air intake,Custom rear strut bar,Perfection clutch,Custom 3inch exhaust,4inch bazooka muffler,,Only 2700lbs,, COME AND GET IT!IF YOU DARE!! Please no Honduuuuhhhs!!! http://www.cardomain.com/ride/858848/2

09-18-2006, 08:35 PM	#4
midwestmk2 3" Exhaust Join Date: May 2005 Location: STL ,MO. Posts: 206	Your best bet is to turn the crank to TDC and make sure the timing marks for the cams are alighned properly..You can then adjust thetiming with a light and the distributor..On the tps though i just moved mine little by little until i was satisfied.. __________________ 83 p-type,5spd,4;10 gears,New 86 cressida 5MGE 195hp,HKS metal head gasket,Cressida injectors,d-port intake runners,No EGR,No cat,Tweaked MAF,Custom cold air intake,Custom rear strut bar,Perfection clutch,Custom 3inch exhaust,4inch bazooka muffler,,Only 2700lbs,, COME AND GET IT!IF YOU DARE!! Please no Honduuuuhhhs!!! http://www.cardomain.com/ride/858848/2

09-18-2006, 09:49 PM	#5
SolidStateS15 Stock Join Date: Sep 2006 Location: SE Maryland Posts: 16	i think i found the problem. the timing is really bad, umm the crank pully bolt wasn't even tight at all so it's been spinning on it's own and throwing off the timing. so now i just need to strip it all down and set it right. just sux on this thing because there is too much crap in the way so u have to remove it all. gonna take longer to remove all the belts and fan then to set the timing itself . i just hope there are no bent valves, is this an interference engine? that could also explain the loud tapping when the engine did run, i though it was just the HLA's but it could be valves. Last edited by SolidStateS15; 09-18-2006 at 10:48 PM.

09-18-2006, 11:25 PM	#6
midwestmk2 3" Exhaust Join Date: May 2005 Location: STL ,MO. Posts: 206	I dont know for sure or not if it is a interference engine or not but i dont think so..If the crank pulley is turning then your going to need a new crank keyway..Hoprfully the keyway slot isnt to hurt or youll be getting yourself a new crank..You can weld them in but it isnt recomended.. __________________ 83 p-type,5spd,4;10 gears,New 86 cressida 5MGE 195hp,HKS metal head gasket,Cressida injectors,d-port intake runners,No EGR,No cat,Tweaked MAF,Custom cold air intake,Custom rear strut bar,Perfection clutch,Custom 3inch exhaust,4inch bazooka muffler,,Only 2700lbs,, COME AND GET IT!IF YOU DARE!! Please no Honduuuuhhhs!!! http://www.cardomain.com/ride/858848/2

09-19-2006, 01:16 AM	#8
midwestmk2 3" Exhaust Join Date: May 2005 Location: STL ,MO. Posts: 206	Keep me posted on your progress if any.. __________________ 83 p-type,5spd,4;10 gears,New 86 cressida 5MGE 195hp,HKS metal head gasket,Cressida injectors,d-port intake runners,No EGR,No cat,Tweaked MAF,Custom cold air intake,Custom rear strut bar,Perfection clutch,Custom 3inch exhaust,4inch bazooka muffler,,Only 2700lbs,, COME AND GET IT!IF YOU DARE!! Please no Honduuuuhhhs!!! http://www.cardomain.com/ride/858848/2

09-22-2006, 05:56 PM	#9
supra1985turbo 3" Exhaust Join Date: Sep 2006 Location: Kingwood, TX Posts: 63	The 5m engine is not an interferance engine. I have a 85 5m and when I first rebuilt the engine I did not want to be going down the 1/4 mile strip and the cam belt brake and mess up the engine. So when I was to that point of lining every thing up I just stuck the belt on and hand turned the engine over about 20 times never hit a valve.

09-23-2006, 12:33 AM	#10
SolidStateS15 Stock Join Date: Sep 2006 Location: SE Maryland Posts: 16	thanks for the info. i actually got it running today which was great. i just had to keep messing with the timing because it would not hold it. i would set it and spin a few times and it would be off again?? not sure what the deal was but it took about 4 times before it would stay together. i got it all back together and took it out for a test run and it was perfect. first time i have actually gotten to drive in it so it felt good.

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