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just workin'
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1,345 Posts
Discussion Starter #1
everyone seems to say that the timing chain can't jump a tooth on the crank, but it seems to me like this is what happened, in order to get 19* the distributer needs to be advanced way too far, almost all the way. i have my 20 links and the pins are at 10 and 12, the sprockets were ziptied to the chain from the begining, and are still and 10 and 12. the car also drives like ****, hesitates then goes, bucks, has irregular revving, but it was running fine with dizzy advanced for like 2 months, then one day started misfiring. so i put in a spare i had, did plugs, wires, fuel filter, cap and rotor. runs better than before but still skips or misses sometimes. the only thing i can think of is the chain jumped a tooth on the crank which supposively isn't possible, although it looks to me like it can. anyone have any ideas?
 

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Coropate greed hater
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4,044 Posts
Just wondering, you are using 91+ octane, right?
 

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just workin'
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Discussion Starter #3
nothing but 93- the octane wouldn't have anything to do with my dizzy needing to be advanced almost all the way, thanks anyway though
 

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Coropate greed hater
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Definitely not, I asked cuz you were talking about how the engine was behaving after you advanced so high up.
 

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just workin'
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Discussion Starter #7
nope it ran it has run irregularly ever since the install, thats why i say it jumped on the crank, harris i know why you asked about the octane rating, but that for sure isn't the prob, i know my cars and i've done cams a few times before, since sr20devolopment and jwt say on their cam install page it can't skip on the crank, but i think that unless it is a worn cam, which i can't verfify because i didn't check for anything but scoring when i put it in the car. has this ever happened to anyone and is the only way to be sure is to remove the front cover? thanks for the replies everyone. i have never had this much trouble with a car, espically an sr20 one....i seem to be able to fix everyone else's but yet not my own, figures
-drew
 

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even if it was off at the crank you should be able to set cylindar 1 to tdc and make the proper adjustments to the chain on the cam sprockets. if they are off it should be noticable to the eye. every link you are off by one the cam sprocket is like 15 degrees or so. so if it did slip at the crank then when it is at tdc the cam wil not be in the right position. i would pu it at tdc and take the chain off the cam sprockets, place the cam in the correct position, pull up all the slack out of the chain and out it on the exhaust side first, and count 20 pins over and put on the intake side. i have done this in the past and it has worked for me. this happened to me after the first motor i assembled.
 

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just workin'
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1,345 Posts
Discussion Starter #9
yeah thats first on the list for tommorow, thanks for the replies, it really seems to be in the right position to me but i'm going to reinstall it tommorow, hopefully this will work cause i hate driving the beater when its not winter yet
 

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just workin'
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1,345 Posts
Discussion Starter #11
nah- it snowed here and i didn't want to work in the snow since i have another car, i will tommorow as long as it itsn't nasty out, i might be coming out to az soon, to check out jobs and visit a friend of mine, i will let you know asap, he lives in east mesa and i was gonna go out that way after christmas. keep in touch
 

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just workin'
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Discussion Starter #12
alright, i have checked this problem out and the cams seem to be timed correctly. 20 pins in between, notches at 10 and 12. i don't know what it could be at this point. i just checked the cat and it is also fine and clean. the only thing that i can think of at this point is my fuel pump going bad, anyone think that should be what i check next? i guess i am becoming a parts changer on this one. i'm gonna try a fuel pump and another maf even though the voltage seems fine. i need some ideas on this one, and btw it my spare distributer this time and it still does this. also new plugs, wires, and fuel filter.
 

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just workin'
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1,345 Posts
Discussion Starter #13
someone help me please, the car will not rev much past 5g's any longer, i guess i have to check fuel pressure and stuff and really get into this one, also maybe a knock sensor? the plugs show signs of running lean, so i think it may be fuel system related, anyone ever had this problem? i don't think it has anything to do with the cams anymore. is it possible that i have 2 bad distributers????i guess but it seems unlikely. any suggestions would be very helpful
 

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just workin'
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1,345 Posts
Discussion Starter #15
it came out of exxd's car, a 91 highport motor with 105k on it, the motor had a rod knock, but the cams seemed ok...i did not measure the lobes of the cams like a dumbass, but from what i have read, if it isn't noticeable, then they should be fine. his motor pulled fine to redline even with the rod kncok for a while. i think i may have a combination of 2 problems. while this thing about revving above 5 g's didn't happen till recently. the car used to run ok most of the time for like 3k miles after the cam swap, but with the dizzy all the way advanced. thats why i thought the timing was off. now this sputtering/misfiring thing happens, so i thought it might be the coil in the dizzy getting weak so i threw in another i had lying around with the same results. i am so frustrated right now, but i gtg put a tranny in a jeep so i don't even have time to fool with it now. any other help would be appreciated. and btw, i have done a few cam install's and never had any problems. i don't get this car at all anymore, and se-r's are usually for me to diagnose...help please
 

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totaled200ser said:
alright, i have checked this problem out and the cams seem to be timed correctly. 20 pins in between, notches at 10 and 12. i don't know what it could be at this point. i just checked the cat and it is also fine and clean. the only thing that i can think of at this point is my fuel pump going bad, anyone think that should be what i check next? i guess i am becoming a parts changer on this one. i'm gonna try a fuel pump and another maf even though the voltage seems fine. i need some ideas on this one, and btw it my spare distributer this time and it still does this. also new plugs, wires, and fuel filter.
First of all, worn cams will not cause this. The cam notches can be at 10 and 12 yet you might still not be at TDC. If the problem started immediately after the cam swap, you can completely reset your timing which will almost guarantee it to run normal again. Manually rotate the crank to 0deg TDC. You can eyeball the marks on the crank pulley. What I did was eyeball the mark and a long screw driver that I inserted into cylinder 1 to make sure it's really TDC. Take out the camshafts, if necessary since the SR20s are interference engines, and rotate them until they point directly away from each other. Take out the distributor cap and make sure the rotor is pointing at spark plug 1. Put back on the cam gears and chain and make sure there is 20pins between the dowel marks on the cam sprockets.... Now this is the most important step. Make damn sure that the chain between the exhaust and crank sprocket is tensed. Then eyeball the timing mark on the crank sprocket to make sure it remains at 0deg while the exhaust notch is at 12oclock. It is extremely easy to be off by a pin since each pin is exactly 10deg and that is not easy to detect on the cam sprocket. However that 10deg translates to 20deg on the crank. So make sure u check the timing marks on the crank. Put back on the chain tensioner and make sure it's unhooked. You can simply push on the tensioner with a screw driver to unhook it. Before you put back on the valve cover. Make sure you give the crank a good number of rotations, the more the safer. Check to see if it remains at 12 and 10 at TDC. If it's slightly off, then you probably skipped 1 tooth or 10deg. Redo it if that's the case.

Don't worry about the timing marks on the chain or about removing the front cover. The marks on the chain are only used when you replace the chain with the front cover removed.
 

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just workin'
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Discussion Starter #17
it has been done already, doesn't seem to help, thanks for the writeup, i drove for like 4000 miles after the cam install and it didn't run great, but with the dist. advanced alot, it would be a 18 degrees, but still had a slight hesitation, seemed like i skipped a tooth to me. then when i check everything is how it should be, are you sure its 20 pins?....thats what i read everywhere, even the alldata.
 

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what engine do you have again? just a regular sr20 or was it a gtir?
 

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totaled200ser said:
its a 98 usdm sr20 in a 95 200


i wish i was closer so i could check this out. have you tried putting the stock cams back in? see if that fixes things. if it does try installing the ones in there now and see if the problem comes back. that should atleast tell you if the problem is with the cams.
 
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