Flat spot when accelerating

[JOSH0315]

hi, I've just rebuilt my 1.6l 92' vitara engine and
it has a flat spot between 2000 and 3000 rpm.
It idles fine and have double checked timing etc,
i've also tryed cleaning the carby.

Once seconds opens its fine its just when accelerating
or cruiseing between 2000 & 3000 rpm.

is there anything i should tweek on the
carby for suit the higher compression.

Can anyone help.

[Harleyindahouse]

Originally Posted by JOSH0315

hi, I've just rebuilt my 1.6l 92' vitara engine and
it has a flat spot between 2000 and 3000 rpm.
It idles fine and have double checked timing etc,
i've also tryed cleaning the carby.

Once seconds opens its fine its just when accelerating
or cruiseing between 2000 & 3000 rpm.

is there anything i should tweek on the
carby for suit the higher compression.

Can anyone help.

Since when have you got Carb????? If you need Throttle body assy I have $75.00

If in fact you have carb though unlikely; carb should have been rebuilt at same time!

Failing that just make certain your firing order is in fact correct for model 8v and 16v are in fact different!

[jtgh]

do you have a vitara and not a sidekick.?
do you have an E28 Vitara 92 , (my epc says they dont exist in 92 , in canada)
first real canada vitara ,was in 99. 1.6L

do you have a vin #
or the body tag to right of battery. if yes what is the vin or the TAG nums.
the last number series tells the market code,.
LLLnnnnn

so what is non stock engine parts.
so what after market parts (non oem) are on car.
what is missing (cat conv?)

that flat spot , if car is bad jetting.
if you changed the way the engines breaths, the flat spot is expected.
if EFI, the same but now its the PROM mappings, in the ECU .

how stock is car.

that is the first order of business.


in some contries, one can import cars from anywhere in the world (not usa)
and in that case , you must tell the VIN or the tag numbers or we cant help you.
GIGO.

cheers.

[Harleyindahouse]

Originally Posted by jtgh

do you have a vitara and not a sidekick.?
do you have an E28 Vitara 92 , (my epc says they dont exist in 92 , in canada)
first real canada vitara ,was in 99. 1.6L

do you have a vin #
or the body tag to right of battery. if yes what is the vin or the TAG nums.
the last number series tells the market code,.
LLLnnnnn

so what is non stock engine parts.
so what after market parts (non oem) are on car.
what is missing (cat conv?)

that flat spot , if car is bad jetting.
if you changed the way the engines breaths, the flat spot is expected.
if EFI, the same but now its the PROM mappings, in the ECU .

how stock is car.

that is the first order of business.


in some contries, one can import cars from anywhere in the world (not usa)
and in that case , you must tell the VIN or the tag numbers or we cant help you.
GIGO.

cheers.

He's in Aussie land....

Unfortunately can't figure out problematic flat spot.... If the engine was rebuilt; it's only as good as the fuel system that said I suggested the carb if in fact he had it should have been rebuilt!

Not really that difficult now, is it to covert carb to EFI; if you know what your doing......having said that no clear understanding of how to resolve this problem has lead him here.... ya think the average understand anything on the matter of EPROM mappings let alone know what to correct?

BTW that round air cleaner; ummm that would likely fit quite nicely on a gray market vehicle and I would have it runnin EFI

[Harleyindahouse]

Originally Posted by jtgh

do you have a vitara and not a sidekick.?
do you have an E28 Vitara 92 , (my epc says they dont exist in 92 , in canada)
first real canada vitara ,was in 99. 1.6L



that flat spot , if car is bad jetting."Assumes ALL adjustments were done", before rejetting.... worked before didn't it?

take out a new piston too and kill the rebuild!!!

if you changed the way the engines breaths, the flat spot is expected.
if EFI, the same but now its the PROM mappings, in the ECU .

All the relevant questions; so what happened to the original motor before the rebuild..... head reworked????



in some contries, one can import cars from anywhere in the world (not usa)
and in that case , you must tell the VIN or the tag numbers or we cant help you.
GIGO.

WELCOME TO FREE TRADE SOCIETY; here in Canada competition even heats up with new vehicles being "gray market" version and oddly enough from same plant of origin but stems from pissin contest between board members.

Think I referenced firing order somewhere before primarily because in fact so many get it wrong as the easiest oversight 1.6 8v/16v.

[jtgh]

thanks for canada tip on politics.
very interesting.
usually
we have canada e28, usa e03 and calif. cars e33 in canada, so now we add graymarket.
i bet the tag on the car will show that it is really one of the 99 Exx market codes.


a we get posts every week here, a gee i mod'd me exhaust , inducting and chucked the cat con, now what.

carb rejet.
efi, new prom
or piggy back time. (fooling ecu 1a)

there is no free lunch, if you mod a car and dont know how to tune it , you are stuck.

it suspect the tag will show exactly what he has, i bet yah.
read body tag

this tag. all you need is tag, (sung to all you need is love ,Beatles)

as the Brits say , its all them fiddly bits that make a difference.

[jtgh]

back to customer
higher compression.
shaved head, and gosh knows what else.
if a carb
and assuming all else is ok and that that the carb is clean and no damaged parts.
then id say the main jet needs to up sized 5%.
in fact a box of jets would allow the tuning to proceed and the flat spot cleared.

the extra power from the higher compression dictates more fuel,
the carb must be turned anytime , the volumetric efficiency is change.
how you do this is up to you.

or in street talk.
if yah mod's z motor, the carbi needs , tweakn.
efi? swap carbi for EFI.

eah?

cheers.

[Harleyindahouse]

OMG now we gotta add a fun page on the oddest tweaks...lol

Cheers JT... Up here they're putting tracks on them now!!!Suppose to be getting some pic's too.... will have to pass them along!

Loved this part...as you said "there is no free lunch, if you mod a car and dont know how to tune it , you are stuck." They will try....lol and funny thing you don't hear how much it cost to fix the screw up's along the way!

[jtgh]

some ,many here say, carbi when they see throttle body and throw all off track. no pun.

yes, i saw a post with a video of the tracks on trackers, hahaha

seriously cool , un north utility.
must be a lot of fun !!

yes, the hidden costs of not having a plan.

thanks for all posts and photos, all is welcome. as always.

cheers.

[jtgh]

if, if ,if
if you have EFI car.
if you have MAF (16v)

Howto-test-a-MAF

you might find this helpful.

maf testing, or how to avoid a $600 repair bill.