Pitchfork wrote:
Questions:
- Does this seem like a good diagnosis?
- Is a carburetor rebuild likely to resolve the issue?
- Could this be a problem with something else like a sensor or ECM?
Welcome Pitchfork!
Do you have a zook too? If not I reckon you need one in your life..
Answer to your questions;
Yes
Maybe and
Yes, although being a carby model I don’t think there will be an ECU driving it.
Diagnosing anything like this is a difficult process and needs to be systematic. The fact it runs on aerostart suggests it’s fuel rather than spark but this CANNOT be relied on as excluding of a spark issue. Confirm you have good spark, a google search will give you tonnes if info on how to do it.
I’m not sure I can find the problem for you without looking at the car, and quick disclaimer that Vitaras aren’t my thing I can’t comment of Vit specific issues.
Old fuel!!!!! First and foremost I’d dump the fuel from the tank and as much of the fuel line as possible. Old fuel doesn’t work and could be your issue, especially if it has been parked up for a while and worked fine before it was parked.
The tank could have water in it or be full of muck. So drain the tank, see what comes out and replenish with good fuel. Change your fuel filters while you’re there, it’s cheap and good practice.
I’d also look at disconnecting the fuel lines and blowing them out with compressed air. BUT!!!! Please be aware that fuel is flammable (even old fuel) and if you blow the lines out make sure you’re not blowing the vapor out onto anything hot. Seems obvious but I reckon it’s still worth a mention. Also, I’d blow the lines out in sections, excluding inline devices such as the fuel pump or filters. You dont have to blast it with 40 thousand PSI of pressure, but clear them out and see what comes out.
New filters and fuel, lines all connected again make sure you’re getting fuel back to the carby. Turn the motor and make sure the pump is pumping the new fuel from the tank all the way through to the carby. I tend to disconnect the fuel line where it enters the carby and poke the hose into an empty bottle, then you can see that the fuel is being pumped right up to the carby. Another disclaimer!!! DONT allow fuel to spill from there onto engine components such as the alternator, it will catch fire and burn your car to the ground. Be very careful if you decide to try this method, I don’t recommend it but I do do it.
Check any vacuum hoses or lines for a leak. A vacuum leak can be difficult to find and cause havoc! I had a vacuum line leaking air and stopped cylinders 1 and 2 misfiring.
If it still doesn’t run I’d suspect dirt or water has gotten into the carby. If you have the knowledge and skills to pull a carby apart and give it a cleanout then great. If not then perhaps consult a carby specialist, or if you can find one to borrow (someone might have a spary they can lend you to put on and try) before you get your carby rebuilt and confirm that this is or isn’t the problem.
See how you go with that lot, report back what you find and what you’ve done. It’s a process of elimination and I’m sure you’ll find the culprit.
