car shudders at partial throttle as turbo spools up...
Apr 21, 2004, 01:49 AM
#16
Evolving Member
Join Date: Jan 2004
Location: Concord
Posts: 206
Likes: 0
Received 0 Likes
on
0 Posts
Originally posted by mhgsx
As much as I don't want to see anyone w/ their car troubles, it really would be a great experiment to see if it turns out to be the BOV or the inlet pipe by only changing out 1 item at a time. It would help MANY people out there. (myself included!!)
I just remember seeing so many threads about irratic MAF readings when a hard inlet pipe had been installed. (regardless of brand) I think the majority conclusion to these mods was that the pipe let too much air in for the MAF to read properly, thus causing the stumble. But the more I think about it, the more I come to the conclusion that it doesn't make any sense at all.
My theory is that the engine vibration is being transmitted to the MAF by using a hard pipe. This is what's causing the mis-readings of the MAF. When I installed the Cusco hard inlet pipe, I noticed how the flexible the accordian inlet pipe was (not to mentin how restrictive it was). Also, the entire airbox that bolts to the MAF rides on rubber bushings to isolate vibration. I remember reading some articles about the WRX having issues with their MAF when an aftermarket induction was installed. Their MAF's used to take a crap, and I believe SCC theorized that it was the vibration that destroyed the MAF.
I'd really like to know if anyone w/ the Samco silicon inlet pipe (if I recall, only Nino sold them) has had any stumbling, part throttle, or idling issues w/ them? Their shape is very close to the designs like the RallyArt, Cusco, AEM, etc hard pipes. If they're not having any problems w/ the Samco unit, then it has to be vibration problems with the MAF.
As much as I don't want to see anyone w/ their car troubles, it really would be a great experiment to see if it turns out to be the BOV or the inlet pipe by only changing out 1 item at a time. It would help MANY people out there. (myself included!!)
I just remember seeing so many threads about irratic MAF readings when a hard inlet pipe had been installed. (regardless of brand) I think the majority conclusion to these mods was that the pipe let too much air in for the MAF to read properly, thus causing the stumble. But the more I think about it, the more I come to the conclusion that it doesn't make any sense at all.
My theory is that the engine vibration is being transmitted to the MAF by using a hard pipe. This is what's causing the mis-readings of the MAF. When I installed the Cusco hard inlet pipe, I noticed how the flexible the accordian inlet pipe was (not to mentin how restrictive it was). Also, the entire airbox that bolts to the MAF rides on rubber bushings to isolate vibration. I remember reading some articles about the WRX having issues with their MAF when an aftermarket induction was installed. Their MAF's used to take a crap, and I believe SCC theorized that it was the vibration that destroyed the MAF.
I'd really like to know if anyone w/ the Samco silicon inlet pipe (if I recall, only Nino sold them) has had any stumbling, part throttle, or idling issues w/ them? Their shape is very close to the designs like the RallyArt, Cusco, AEM, etc hard pipes. If they're not having any problems w/ the Samco unit, then it has to be vibration problems with the MAF.
so, with regard to the MAF vibration, what are the race teams doing for induction pieces? are they using soft hose with cushy filter mounts?
also, it seems to me that if a MAF sensor was so prone to err because of shock, our cars would all be running like crap over bot-dots, big bumps, and probably even hard launches.
it seems more likely to me that the error is due, at least in part, by the lack of the the stock airbox. The inlet area before the maf was probably designed that way for a reason.
I remember many in the 5.0 crowd having great success with simply turning their MAF's in the hoses. Mustang inlet hoses are perfectly round, so you can spin the sensor around to any clocking position.
just as you slosh down a waterslide, so does air flow through a pipe. maybe the MAF element could be in a steady stream of air or in a relative dead zone, depending on this orientation. i think the thing to do for most people was to clock the sensor at 6 o'clock.
Apr 21, 2004, 06:31 AM
#18
Evolved Member
iTrader: (10)
Join Date: Sep 2003
Location: Millersburg, OHIO
Posts: 881
Likes: 0
Received 0 Likes
on
0 Posts
mine had that sound and went away between the mods of fuel pump, cat delete, and/or Dynoflash. not sure but one of those mods made it stop shuttering and now its a smooth hiss sound.
Apr 21, 2004, 08:09 AM
#19
Newbie
Join Date: Jul 2003
Posts: 9
Likes: 0
Received 0 Likes
on
0 Posts
Originally posted by evomind
this cant be normal........
this cant be normal........
It does sound however like the BOV in this case based on the fact that you are still running the stock turbo like SHAPEGSX said. Seems very odd though that it started happening after a boost leak was fixed.? I swear sometimes our cars can do the wierdist ish.
Hope you get it figured out soon
joshua
Apr 21, 2004, 08:24 AM
#20
Evolving Member
Thread Starter
Join Date: Jan 2004
Location: chicago
Posts: 135
Likes: 0
Received 0 Likes
on
0 Posts
good info guys.....thanks.
ams believes its the bov also.....too bad they are out of stock on them till friday.
i am aware of the mustang trick of turning the maf....thats what i was gonna do after i get the studdering problem fixed. ill probably try to add more fuel down low first.....
well, i hope a different/better bov cures this cause its getting very frustrating....
thanks again for the help.
ams believes its the bov also.....too bad they are out of stock on them till friday.
i am aware of the mustang trick of turning the maf....thats what i was gonna do after i get the studdering problem fixed. ill probably try to add more fuel down low first.....
well, i hope a different/better bov cures this cause its getting very frustrating....
thanks again for the help.
Apr 21, 2004, 08:29 AM
#21
BEFORE you kill yourself trying to figure out the problem... REPLACE YOUR PLUGS.. I used to get the studdering/surging and it happened one day, never gave it much thought but it never went away.. When I replaced the plugs with colder ones, gapped tight at .026, the car idled smoother after it warmed up, and the surging and stumbling at part throttle went away completely..
You probably have a bit of mileage on those plugs, and when I took mine out after 7000 miles, they were coked and pretty fouled.. You could clean an re-gap your stock plugs, but as soon as you say BUSCHUR RACING stages, right away I think colder plugs (one step)
ANYTHING that effects the way the engine runs (from leaks to modifications) can be enough to foul the plugs in some way.. At leas you can rule it out, but its a simple thing to do, takes under 20 minutes to gap and install a new set of plugs.
You probably have a bit of mileage on those plugs, and when I took mine out after 7000 miles, they were coked and pretty fouled.. You could clean an re-gap your stock plugs, but as soon as you say BUSCHUR RACING stages, right away I think colder plugs (one step)
ANYTHING that effects the way the engine runs (from leaks to modifications) can be enough to foul the plugs in some way.. At leas you can rule it out, but its a simple thing to do, takes under 20 minutes to gap and install a new set of plugs.
Apr 21, 2004, 03:13 PM
#22
Originally posted by Turbocake
so, with regard to the MAF vibration, what are the race teams doing for induction pieces? are they using soft hose with cushy filter mounts?
also, it seems to me that if a MAF sensor was so prone to err because of shock, our cars would all be running like crap over bot-dots, big bumps, and probably even hard launches.
it seems more likely to me that the error is due, at least in part, by the lack of the the stock airbox. The inlet area before the maf was probably designed that way for a reason.
I remember many in the 5.0 crowd having great success with simply turning their MAF's in the hoses. Mustang inlet hoses are perfectly round, so you can spin the sensor around to any clocking position.
just as you slosh down a waterslide, so does air flow through a pipe. maybe the MAF element could be in a steady stream of air or in a relative dead zone, depending on this orientation. i think the thing to do for most people was to clock the sensor at 6 o'clock.
so, with regard to the MAF vibration, what are the race teams doing for induction pieces? are they using soft hose with cushy filter mounts?
also, it seems to me that if a MAF sensor was so prone to err because of shock, our cars would all be running like crap over bot-dots, big bumps, and probably even hard launches.
it seems more likely to me that the error is due, at least in part, by the lack of the the stock airbox. The inlet area before the maf was probably designed that way for a reason.
I remember many in the 5.0 crowd having great success with simply turning their MAF's in the hoses. Mustang inlet hoses are perfectly round, so you can spin the sensor around to any clocking position.
just as you slosh down a waterslide, so does air flow through a pipe. maybe the MAF element could be in a steady stream of air or in a relative dead zone, depending on this orientation. i think the thing to do for most people was to clock the sensor at 6 o'clock.
Also consider the fact that part throttle driving means nothing to them. They're either on the brakes or at WOT 95% of the time.
The airbox and maf seems pretty well isolated from engine vibration. The box itself sits on soft rubber bushings. And the accordian inlet hose is really pliable.
I really wish someone with the Samco unit would chime in with their experiences.
For the record, I have the Cusco unit attached to the stock airbox. I don't have this problem, but I've noticed the idle to sometimes be a bit flakey, when the car is hot started.
Apr 22, 2004, 05:47 AM
#23
Originally posted by MalibuJack
BEFORE you kill yourself trying to figure out the problem... REPLACE YOUR PLUGS.. I used to get the studdering/surging and it happened one day, never gave it much thought but it never went away.. When I replaced the plugs with colder ones, gapped tight at .026, the car idled smoother after it warmed up, and the surging and stumbling at part throttle went away completely..
You probably have a bit of mileage on those plugs, and when I took mine out after 7000 miles, they were coked and pretty fouled.. You could clean an re-gap your stock plugs, but as soon as you say BUSCHUR RACING stages, right away I think colder plugs (one step)
ANYTHING that effects the way the engine runs (from leaks to modifications) can be enough to foul the plugs in some way.. At leas you can rule it out, but its a simple thing to do, takes under 20 minutes to gap and install a new set of plugs.
BEFORE you kill yourself trying to figure out the problem... REPLACE YOUR PLUGS.. I used to get the studdering/surging and it happened one day, never gave it much thought but it never went away.. When I replaced the plugs with colder ones, gapped tight at .026, the car idled smoother after it warmed up, and the surging and stumbling at part throttle went away completely..
You probably have a bit of mileage on those plugs, and when I took mine out after 7000 miles, they were coked and pretty fouled.. You could clean an re-gap your stock plugs, but as soon as you say BUSCHUR RACING stages, right away I think colder plugs (one step)
ANYTHING that effects the way the engine runs (from leaks to modifications) can be enough to foul the plugs in some way.. At leas you can rule it out, but its a simple thing to do, takes under 20 minutes to gap and install a new set of plugs.
Thanks
Thread
Thread Starter
Forum
Replies
Last Post
scottatyamaha
Evo X Engine / Turbo / Drivetrain
15
Oct 15, 2008 02:51 PM
Hypreshr
Evo Engine / Turbo / Drivetrain
3
Sep 11, 2003 10:19 AM
