[Jimgub]

Hey folks, only had the vitara about 4 months, converted from hilux and so far it's an awesome little car! However since I brought the car it's had issues with chugging and appearing to struggle for fuel on hills and at highway speeds. I've done a lot to the car since I've had it and the car has improved a lot since then but it still struggles at or over 90ks or so depending on hills/wind/weather/towing and its got me puzzled...

So far I have gapped and cleaned plugs, replaced leads and dizzy cap, cleaned rotor button, replaced fuel filter, set timing to 8-9 degrees, replaced the timing belt and recently put a carby kit through it and set idle to 800rpm as well as block everything to do with the egr (car has extractors anyways) and may have forgotten a thing or 2. Im new to zooks as well as carbys so it's all been fun but it's a great car to work on, so far so good.

The car is running better than ever, accelerates really well, I can feel the secondaries kick in, and I can feel much better power but after all this I towed half a 6x4 load of wood 30km and it coughed and struggled at 80-90 when I pushed past half to three quarters throttle.

Sorry for the essay I just thought I'd explain as best I could! Not exactly sure where to look next, Ive taken the fuel hose to the carby off whilst the car was running into a container for a few seconds and it seemed like a decent flow but I can't say I know what it should look like so perhaps new fuel pump. Either that or I'm thinking the jets in the carby may be to small to suit extractors??

Any suggestions would be greatly appreciated! Starting to run out of ideas with it and staring at it isn't helping anymore!

[MrRocky]

Clean your fuel tank

[Jimgub]

Repeatedly blocking fuel pick up? I'll give it a go thanks mate! I'll let ya know

[Jimgub]

No difference removed fuel tank, drained tank out the fuel gauge sender hole into a clean bucket through white cotton, there was a little sediment and a few flakes it not a great deal. Rinsed the tank well with clean fuel then dried it and blew it out with the compressor, inside of tank looked good, bugger all flaking and looked nice and clean. Took the fuel filter out (maybe 5000kms old) had bugger all crud in it and flowed really well but flushed it backwards and disconnected all the fuel lines at both ends and blew them out with the compressor. Put it all back together, ran shit for a bit then was fine, let it warm up and took it for a strap and same deal. Im happy with how it is since carby kit and so on and without a trailer it's really punchy at anything under 100 but over that if I give it over 3/4 throttle it breaks down and I know when I hitch up the trailer it'll be a bitch again.... I don't expect to go over 100 or even 90 with the trailer but I should be able to put my foot flat and not have it cough and break down I reckon or is that just zook life? Haha

[Gwagensteve]

Replace fuel pump.

[MrRocky]

Also could be a blocked cat

[ozzycouch]

Just fishing for information...
What size tires are you running?
What gear are you in when you floor it from 100?

[Jimgub]

Blocked cat? Do they even need to run a cat? Aah running 235/75 r15s on alloy rims. I generally grab 5th at a touch over 80 odd. Rarely gets revved past 3500rpm and I don't think I've seen it far past 4000. If I'm in 4th gear and look for much more than 3300 revs it tends to struggle. Having had the lux, revving a car past 3 grand feels like it hurts... it gets better and better til it starts to cough I can't wait to see it working properly.... thinking I'll get a new fuel pump next week on Thursday when cash permits it's about the last thing I can think of but would be annoying if it wasn't the problem

[MrRocky]

U be suprised what a chunk of honeycomb rattling around in the cat housing can do, can also create quite a hard to pick issue and reduced my speed to 5km phr till i punched holes in the side to get home

[shiv]

Jimgub wrote:

Blocked cat? Do they even need to run a cat? Aah running 235/75 r15s on alloy rims. I generally grab 5th at a touch over 80 odd. Rarely gets revved past 3500rpm and I don't think I've seen it far past 4000. If I'm in 4th gear and look for much more than 3300 revs it tends to struggle. Having had the lux, revving a car past 3 grand feels like it hurts... it gets better and better til it starts to cough I can't wait to see it working properly.... thinking I'll get a new fuel pump next week on Thursday when cash permits it's about the last thing I can think of but would be annoying if it wasn't the problem

I think the stock revs for the 1.6 is about 3600 rpm? When i had smaller tyres on my G16B i would sit on 4k rpm all day long and then go up to 4.5k to over take or build momentum for a hill ect.

[MrRocky]

My g16b sits bang on 4000rpm @ 100

[rustyzook]

My g16b sits bang on 4900 at 110. Never worrys it one bit.

[shiv]

I dont feel as bad now lol

[jdk81]

The stock exhausts can block up easily too.
A few tiny bits of the cat can really restrict the exhaust gasses

[Jimgub]

Yeah makes my 3200 @ 100 seem better and feel a lot better about letting it rev, took it bush today and needed every bit of 4 grand in the mud! I had a look at the cat and a closer look shows a bit of interesting work... Exhaust looks to be 2 inch from extractors to cat, then there's a short section of about 1 1/4 inch around 8 inches long joined to 2 inch for the rest of the exhaust. The works been done well but it can't be right... Thinking about taking the exhaust off tomorrow and removing the cat and dodgy bit altogether and welding in a section of pipe to replace it. Any reason why the section of pipe might be there or why I shouldn't delete the cat and so forth?? Thanks again for the help folks if anything it all makes it a better car which is basically what I've gotta do. Big move coming soon from vic to nsw need the car right haha

[rustyzook]

shiv wrote:

I dont feel as bad now lol

6.5s and 31s. It's slow and loud.

Have you checked the carb mate? Secondary's are not blocked, or your float sticking?

[Gwagensteve]

Don't delete the cat if you want the car "right" and need to transfer registration. There is a significant fine for removing a catalytic converter.

There is no reason why a section of 1 1/4" pipe would be in there. Stock diameter is more than that. (Not a lot more, but more)

I can't comment on whether thats the cause of your problem though.

A G16A should rev cleanly and strongly to about 5500rpm. Above that they feel a bit restricted and doughy, but will rev to over 6000 without a problem.

Here's the thing though - it sounds like you're complaining of poor performance once the motor has been on load for a little while - i.e once you get to speed on the freeway or on hills. I believe this is most likely a fuel delivery problem. The car will run fine and will take load for short periods, but once loaded for any period of time the fuel pump can't keep up and the car bogs or performs poorly. It's not an uncommon problem.

[losfer]

Exactly what i told him steve.

Sent from my SM-G935F using Tapatalk

[Jimgub]

Awesome info Steve cheers mate yeah fuel is where I think the issues lies... won't be selling or requiring roadworthy anytime soon, I plan on having the car a long time. The attachment happened quick with the vitara haha and down the line I'll be looking at engine conversion and so forth but that's 12 months or more away at least.

If legalities are the only problem with the cat I think I'll remove the whole section with that little bit of pipe for now and replace the fuel pump this week. Like ya say Steve as the pump wears out it might start to struggle, followed by the jets sucking the bowl dry and killing the car til it catches back up and fills the bowl again. Thanks again for the help folks enjoying learning more about these zooks I'm hooked

[Jimgub]

Been a month or so since the troubles, after I replaced the fuel pump the car ran much better but still sometimes on long hauls up big hills at highway speeds, she sometimes coughs and plays up. After I did the carby kit I may have played with the wrong screws... Ive now fixed/tuned it as best I can according to another post on the forum and once again, improvement everywhere but where I'm looking for it! I've cleaned the spark plugs and I'll spend a couple weeks playing with the fuel mixture perhaps. Also it seems extra nasty on cold mornings as in I have to hold the revs up for a bit before it will idle

[Jerryx4]

Hey guys, my G16A was filling whole motor after 1 day sitting with fuel, tried all the above, pump carb kit, vacc lines all of it. Have just tonight been told check tank pressure and fuel cap. Cap on i take off fuel line, fuel pisses everywhere, take cap off.....nothing. I look in fuel cap and notice it has a small disc type valve but it seems to have slipped through the spring to the top of the cap blocking the pressure hole. I'm hoping a new cap fixes my issue.... Mine also bogs at around 2700-3000rpm so hopefully this may fix that too as maybe on opening the secondary its firing shitloads of fuel in making it bog down? anyway worth a try....feeling more positive now after 8 months of ripping my hair out changing oil thinking its fixed only to have it fill with fuel again!

[Gwagensteve]

Filling which part of the motor after 1 day sitting with fuel? the crankcase?

That's normally a fuel pump related issue, but if you've eliminated that, I'd suggest you have two problems. Someone has messed with the evaporative system ( the system that carries fuel vapour from the tank, through the charcoal canister and burns it) and/or the fuel cutoff solenoid is faulty.

The caps aren't completely sealed, but they're close. however a sealed cap will normally lead to a vacuum in the tank as fuel is burned. Pressure in the tank implies the evap system has been plugged.

[Jerryx4]

Ok cheers dude, is there any way i can f off the canister all together as I have considered this in the past

[Gwagensteve]

Why on earth would you want to do that? It's there to filter fuel vapour entering your engine. It doesn't reduce performance, it doesn't even have moving parts. it just sits there doing its job. (So long as it's not blocked (which can happen and could cause the issues you're having)

I reckon someone, or yourself, has fiddled with the tanks vapour system and it's created this problem.

alternatively/additionally, is the fuel return line flowing freely?

[Jerryx4]

all fuel lines flowing good, just having the canister there is annoying to get into the alt etc and so im learning some vacc hoses etc when blocked off mean one less pita thing to deal with at some stage lol. My tank is pressurising for a reason I don't know & if it is assisting the problem I'd rather eliminate it if simple enough. This problem jsut arose all of a sudden one time I cmae out and turned car over and it was solid, i took out a plug and turned by hand and fuel shot out. ever since I have attempted to solve this...and with the cap off the tank it seems to have stopped the forced flow which im assuming is enough pressure to push the needle and float down thus forcing the motor to fill