Welcome to the SR20 Community Forum - The Dash.
Register
SR20 forum logo

Thread: Why is my vvl so hard to start

+ Reply To Thread
Posts: 1-10 of 32
2011-12-17 16:04:48
#1
Why is my vvl so hard to start
Anytime im starting my car it has to turn the engine over several times before it starts.

and not just when its starting for the first time for the day, but all the time..

if i shut it off now, and start again right away, yea, it will start a little faster.

other vvl owners tht i know dont have this problem. (only cold start)
2011-12-17 16:37:56
#2
You may have bad injectors. Leaks when the engine is off
2011-12-17 17:05:47
#3
Battery problem? My DE woudn't start well either, until I replaced the battery.
2011-12-17 19:14:36
#4
Battery grounds. If bettery is in the trunk, change it back to the front.
2011-12-17 19:21:20
#5
Check your spark plugs. Every time I replace mine she starts up a lot easier.
2011-12-17 19:36:22
#6
I've seen the same problem on most of the cars with a chipped ECU's
Last edited by macakin on 2011-12-17 at 19-46-05.
2011-12-18 00:18:04
#7
Mmm, I doubt its a tune thing. Both my car and buddies started without any hesitation or trouble. The most common for poor or hesitation to start during cranking is a weak battery, bad ground cables, usually common with batteries in the trunk done crappy. Problem lies when your cranking on a weak battery its sucking up most of the battery power thats left and dropping the voltage sometimes to 9-10 volts during cranking and not enough juice to supply a good spark or sometimes not enough juice for the ecu to stay powered on correctly. Usually it hesitates for a bit until the starter gets up to full speed cranking and then in between compression strokes it tries to fire once some stress is taken off the starter.

Could be a number of things though, plugs not gapped correctly making cold starts or warm starts hard, dirty injectors, fueling problem, and several others.
2011-12-18 02:41:33
#8
Originally Posted by macakin
I've seen the same problem on most of the cars with a chipped ECU's


It's all in the tune. If you have a chipped ECU but stock injectors/maf then you should be fine.

Technical reason as to why:
Our ecu's are tuned for 259cc injectors. They have cranking enrichment and cold start tables. They basically dump more fuel when your cranking it, or when you cold start it. This enrichment is part of the calculation to get a the total amount of fuel that injectors should spray.

When you install bigger injectors (333cc on VE's), you will have more fuel being dumped per pulse width. This is why you need to adjust your K value to, otherwise you will be too rich. By adjusting your K value you are adjusting another variable that is part of the calculation to get the total amount of fuel to spray. Adjusting the K value is a good way to adjust your AFR's across the whole fuel map, but doesn't mean your cranking and cold start enrichment will be right anymore.

Thus you need to adjust those tables for the car to run like it did before. Now if you adjust your K value to be too lean, then you will actually have to add to the enrichment tables otherwise you will have lean spots while cranking/cold driving.

Same goes with the MAF, you mess with the K value when you install a new MAF thus you mess with all of the calculations.
2011-12-18 02:42:35
#9
fuel pump....I call it....yah I went there
2011-12-18 02:45:07
#10
Originally Posted by Vadim
It's all in the tune. If you have a chipped ECU but stock injectors/maf then you should be fine.

Technical reason as to why:
Our ecu's are tuned for 259cc injectors. They have cranking enrichment and cold start tables. They basically dump more fuel when your cranking it, or when you cold start it. This enrichment is part of the calculation to get a the total amount of fuel that injectors should spray.

When you install bigger injectors (333cc on VE's), you will have more fuel being dumped per pulse width. This is why you need to adjust your K value to, otherwise you will be too rich. By adjusting your K value you are adjusting another variable that is part of the calculation to get the total amount of fuel to spray. Adjusting the K value is a good way to adjust your AFR's across the whole fuel map, but doesn't mean your cranking and cold start enrichment will be right anymore.

Thus you need to adjust those tables for the car to run like it did before. Now if you adjust your K value to be too lean, then you will actually have to add to the enrichment tables otherwise you will have lean spots while cranking/cold driving.

Same goes with the MAF, you mess with the K value when you install a new MAF thus you mess with all of the calculations.


this.
+ Reply To Thread
  • [Type to search users.]
  • Quick Reply
    Thread Information
    There are currently ? users browsing this thread. (? members & ? guests)
    StubUserName

    Back to top