4g91+1.5vdo GB=High RPM cruising=high FC??

chromeless1

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hey guys..need help on my car..

prev my car stock std wira 1.5vdo manual..last year change to 4g91 lantai..so use back the 1.5 gb+1.6flywheel..so using the car and felt the FC was even worse then my ex-vdo engine (should be the other way around right?) then i started fiddling the the minor2 stuffs..wiring go check..fuel pump..tb la..this la..that laa..and i still cant find whats wrong..

and later while driving i suddenly surprise to check my rpm when crusing..usually it suppose to be 100km/h rpm is at 3000rpm..but i check 100km/h is at 3900rpm!!! wow!! i am totally shocked!!
so thats why my FC is sky high...check meter they say ok..

so sifu2 can help on this?some say ratio not ngam..but got frens who use 1.8&1.6 with 1.3gb though topspeed not so good..but still got 100km/h @ 3000rpm..what so diff with the 1.5gb? and does the flywheel would take effect? a 1.6flywheel pared with a 1.5gb??
 
When u say FC is sky high, giv some figures la... I mean, u can feel it's high, but others might feel it's normal/acceptable ma...
Also, r u using 4g91 wiring n ECU?? airflow sensor??? Exhaust/O2 sensor faulty or not???

I did encountered before last time when I was using 4g91... FC suddenly increases (can't remember figure, but increase significantly)... Only thing not right is my Apexi Pen Timer a/f not working... Got the O2 sensor changed n everything back to normal... Btw, engine check light din even come out dat time!!!!
 
hey there calvin...well..ive been fiddling with all that u hv mentioned..changd ecu, changd wiring..changd airflow..o2 checked..plug cables..u name it..it is not related to that sort of bits..actually was due to higher rpm to be used by me in norm speeds...like example that i mentiond earlier about driving 100km/h with rpm @ 3900..which would probably means more fuel needed to maintain the usual 'eco' spot for norm drivers would hv. while in go stop roads..it does feel light..but in cruising..i cant cruise the way i norm do to save fuel.. right now cruising in around 80km/h which is @ about 3500rpm in 5th gear..normally ill do 12xkm/h with that kind of rpm..

so still abit frustrated coz dont know what to do...a fren told to go change FD..but some say check flywheel..huhuh..
 
how did changing just your engine physically affect your gear ratios? It shouldn't have changed at all.

what wiring, ECU and meter panel are you using?
 
well tks...thats why im so confused...the wiring,ecu are all from 4g91..even rojak with other 4g9x family also wouldnt hv this kind of effect..well..i guess myb gonna check my clutch then..
its been pretty worn out.. (or should i say gone already) huhu..they say also would effect the rpm reading if clutch slip is it?
 
clutch slip, in its simplest explanation; accelerate, rpm rises but car doesn't go. Try this in the higher gears where there's more load and you'll notice it. Just change it since you can confidently say its GONE... :banghead:

Also, the Wira speedo reads till 200km/h. Most likely you've ended up with a 4g91 speedo that reads only till 180km/h, which would mean the scale is off. So unless you've swapped out the little gear in the gb that goes to the meter, it'll be over-reading...
 
hehe..thanx tks..will be changing the clutch plate+cover this weekend..and bout the speedo gear that u r talking about..will try to sort out too later..dunno how to ask shops about it..later they say "all same maa.."...
 
clutch cover, plate, don't forget the clutch bearing and flywheel oil seal. Inexpensive items compared to the labor costs you'll need to spend on (again) should they fail mid-way through the lifespan of your clutch. And while it may seem like a no-brainer to change those at the same time, believe me...some workshops won't change it on purpose if you don't ask them to.

On another note...if your workshop is telling you all speedo gears are the same... :banghead: i think its time you stop patronizing their shop!

All the best!
 
Chrome,do let us know what the outcome is.Learn from the problems shared.. Hope your problems will be settled once and for all...
 
well guys..a quick update..changed new plates+cover+bearing+seals...the result is still the same..so guess hv to change the final drive lor...hv a check firts to see if the fd had been touched or not..any rough ideas of how to differentiate the fd's of mitsu&protons GBs?
 
have you even checked your speedo gear and the meter yet? there's a simple rule to troubleshooting. Start with the simplest things first! You haven't even told us what meter you're using.

Also, go check your gearbox code and post it here. Look from the top, almost directly below your cam angle sensor and you should see a flattened part on the gearbox. Codes should be there.

To see a list, go http://www.ben9166.com/2010/08/mitsubishi-gearbox-information.html. Credits to whoever's blog that is.

Cheers
 
opss..sory tks..

i use 4g9x meter and the gear is from a 4g9x also..thanx
and the code is F5M221 VRJE..from 1.5 vdo year 2004
 
opss..sory tks..

i use 4g9x meter and the gear is from a 4g9x also..thanx
and the code is F5M221 VRJE..from 1.5 vdo year 2004
like tks said, it's your meter problem. you can continue using the meter, but you have to change the speed sensor that plug to gearbox with 4G9x sensor, otherwise you having inaccurate reading of your actual speed, like now.
 
Hi, my car is a 1991 Saga Aeroback 1.5 Automatic Aisan Carb 4G15 12V engine. To maintain a constant
100km/h on flat road, i need a 3.5k rpm. Not bad for an auto eh? FC is 14.7KM/L at 60% highway.
Engine oil using the thick 20W 50 dino oil. Engine still ok, got water dripping during morning warming up.
Top speed still unknown, never floor it coz beyond 110km/h wheel already start to shake. I just got this
car like 1 month ago. Yesterday baru change all 4 tires and absorber. After raya will back to KL, so will test power on the North-South Plus Highway. Btw, anyone know my fuel tank capacity?
 
3900 rpm reli gila worr... 3000 is normal at 100 km/h la... Maybe its gear ratios... In the gearbox or final drive...
 
haha..yup..gila weii..well..im gonna try out changing the final drive soon, myb next week..
guys...is smaller final gear is for long ratios & bigger for short ratios right? or the other way around? coz ive checked at GB manuals of std proton gb f5m211 vrje final drive is 4.322..and as i know mivec is 4.5xx something right (which is famous for it's close/short ratios)? and std 1.6/1.8 manual gb's final drive is 4.0xx issit?
kinda confuse coz some say 1.6 fd is longer (should be smaller right?) but hv friends quoting 1.6's fd is bigger....
huh...

any sifu can help?
 
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i see my sister bf's new honda 2000rpm already reach 100km/h while my old saga
needs 3500rpm to reach that speed. Geram nia...
 
hehehe..of coz laa..new honda maa..engine cc bigger..so gearing of coz better (performance&cruising)..old cars like us hv to rojak2 la to get that kind of rpm..huhuhuh
 

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