[Gadzuks]

Hi guys,

I'm having some troubles with the old girl at the moment (the car that is...) and am hoping to get some advice.

The car:
1997 Vitara JX LWB G16B. Lifted 2 inch and has 235/75s and stock tires. Problem occurs with both sets of wheels. Daily drive it highway and backroads to work, 320000km on the clock.

The problem:
Boggs down/retards (according to the apprentice mechanic..) when you accelerate more than gently until it hits 2.5 to 3K RPM then goes fine. It's like you accelerate and it seems like it's holding itself back then suddenly, off we go! No other problem with how it drives.

Other info:
Had a full new exhaust about a month ago
Has a new dizzy, plugs, fuel pump about 2 months ago
Has had oil in the plug tubes - not sure if it is good now, will check this weekend
Pings a bit when it pulling hard up a hill.

This has been a bit of a reoccurring problem. Long story short:
Drove it up the blue mountains for half hour with no problems - going for a trip. Stoped for food and when I got back in it wouldn't pull up the hill unless low range and +3000 RPM.
Mechanics cleaned the O2 sensor, plug tubes and something else I can't recall right now and it seemed to be fine
A week later it started coming back - just a little miss at first then got to the point where I had to hold it at 3K and slide the shit outa the clutch to get it moving. If you're really gentle (on the flat and very slow acceleration) it'll get going as normal.
Took it for a service and the mechanics played with the timing - it was firing TDC(!). they set it to 5 deg and it helped, set it to 10 deg and it mostly went away. Has now come back in the same gradual way. The apprentice said it looked to him like the ECU would retard the engine at low revs under load before it let it go properly.

Quick info about the dizzy (another saga of incompetent mechanics) in case it's related and to explain TDC:
She cut out on the HWY one day. Mobile mechanic reckoned it was the dizzy.
After a LOT of fcuking around got a new coil pack and crank angle sensor and rebuilt it and put it in myself. Still didn't go.
Got the mobile mech to look and he couldn't figure it out.
Got a friend who builds race car engines to help and we traced it to the FI fuse. Then traced that to the fuel pump being in failure mode. New fuse and Fuel pump and she was away. Nobody checked the timing (I don't know how/have the gear and had asked the mobile mechanic to do it ). I'd managed to set it to TDC by fluke.
2 weeks (about) later the above issue starts.

I'm planning on taking it back to the mechanics but I'd be super appreciative if you guys could make some suggestions. Would be good if I could point them straight at a few possible things. Might also be something easy for me and a mate to sort out.

Cheers.

[Gwagensteve]

The FI fuse is quite large (15A or something)

It's possible this was wiped out when the fuel pump failed, but it's a bit odd.

Yes, oil in the plug tubes would do it - you're not getting spark at the plugs - same way a car with a wet distributor will idle but as soon as you load it up it dies.

If they're dry and the plug boots are in good condition, then look at the coil

sounds more like the ignition side than the fuel side, but I'll assume the correct fuel pump was fitted/fittings tight/FPR in known good condition? (These are starting to give trouble)

Steve.

[Gadzuks]

thanks for the info Steve. Yep, the fuel pump was blowing the FI fuse. We tested the lines and found the fuel pump was shorting. As I'm sure you know, the dizzy, engine management and fuel pump are all supplied through the FI fuse. When it went the entire car really did stop.

I'm 95% sure the correct pump went in and that the fittings are tight. I've no idea about the pressure regulator. I'll check it out and also check the plug tubes are clean. If there is oil getting in there it's most likely the rocker cover gasket, right?

Cheers.

[Gwagensteve]

I guess, in a manner of speaking, you're right about the FI fuse - but most importantly, with that fuse gone the ECU isn't powered so it doesn't matter what else runs from that circuit - the car will never run. Fuel pump, distributor, coil etc could all still be powered, engine still won't run.

Not sure - an exploded view from the FSM will tell you a leak path into the spark plug tubes.

Consider that if arcing is a problem, you'll get a carbon build up on the plug boots that will make arcing and breakdown more prevalent going forward.

[30ONA]

Checked for Vacuum leak(s)?

[Gadzuks]

Nup, haven't. Will see about checking that too.

[losfer]

i would be checking crankshaft keyway seen it too many times. take off the timing cover and look for a red dust this is one of the signs of a flogged keyway. Remove the lower sprocket and visually check key and keyways.

[kenzook]

I read that u changed plugs and dizzy but not the leads? I think you're arcing out under load like suggested above.
By baleno/sierra is currently breaking down under load (light pedal and high revs are ok) and all I've read suggests coil packs or leads under them failing.


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