V6 - Pre-Service Questions

[JudgeFoozle]

Hi All,

Using our Bongo as a daily driver (600km+ per week) and it has been faultless up to the start of this month - service is due in under 3000km, but I'm going to go a bit early as a couple of things have come up:

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The Bongo stalled in a road puddle at the start of March - a road puddle that turned out to be a "mini lake" caused by a flash flood. I managed to start her back up, sat at side of road for a half hour or so, then drove home, but with less power than normal. The next morning, power was back, but it was running a small bit noisier. Only noticeable because it had been very smooth beforehand. This has slowly become noiser, but I think the exhaust may also have something to do with this...

Would one solution be changing oil/fuel/air filters? They were all done at last service, but would the water incident have caused it to sound a bit "rougher"?

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There's smell of petrol fumes if I start up and leave the van parked for a minute before driving away. I suspect something with the exhaust - it doesn't rattle, more a low vibration from the mid section that has gotten louder in the last two weeks.

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Also, the 'HEAT' red light on the dash lit up when I stalled - and has remained on since.

I've searched about this, and it seems to have happened other V6 owners who have stalled in water - but it's not a sign of imminent danger? Anything here I should check or be worried about though?

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Finally, the 'AIRBAG' light is also flashing - sequence of 6, a gap, then repeat. This has happened only 2 times in the last 2 weeks, but it's something I want to get sorted.

Again, I've done a bit of research on the site about this but there seems to be no definite solution, more a few possible ones! Will be trying these out.

My mechanic is a neighbour who's a great help even though this is his first Bongo to work on - he's happy to take notes/pointers on Bongo-specific areas though so no worries there.

Any pointers on any of the above??

[haydn callow]

O.k. This could be at least part of the problem....when you went through the flood you got the ignition system wet.....this caused it to be firing on (probably) not all cylinders......this causes unburnt fuel to enter the catalytic converter which causes it to overheat the converter and the heat light comes on....

That's what happened to me in my MX5... A second hand cat fixed it

I'm assuming yours is a late model V6 and the HEAT. light refers to the cat and not the glow plugs.

If V6s never had a cat fitted I'm talking rubbish.

[haydn callow]

On the other hand you may when it got wet, caused the ignition to track to earth......remove all leads one at a time and really clean them......at both ends, also clean the distributor cap inside and out....
You could only be firing on 4 or 5 cylinders....this would cause a slight drop in power and noise.

[JudgeFoozle]

Should have said, it's a 1997 V6.

Thanks for the suggestions Haydn, will add those to the checklist.

[Simon Jones]

I would consider giving the whole ignition system a revamp: rotor arm, dizzy cap, all 7 HT leads and plugs. For sudden cut out when getting the engine wet it could be the crank position sensor which is quite exposed at the front of the engine (shown below). The poor running, it sounds like it been mis-firing on a cylinder or two which is something that should not be ignored as it can do damage to the engine and unburnt fuel getting into the catalytic converter can ruin it which is quite expensive to replace. Another thing that can destroy a cat is a sudden dunking in cold water which could easily crack the internal elements.

[mikeWalsall]

On an 18 year old motor may be prudent to change the dizzy cap / rotor/ plug leads /plugs anyway ..

Checking my speedo/ circuit board for bulb holder contact 'tram lines' .. my1998 V6 as never had a 'HEAT' warning light for the cat fitted ..



Once again .. given the Bongos age and weather conditions when the problems arouse there may be internal problems with the cat .. which can be re placed (or re conditioned)

This re conditioning company is local to me ...

http://www.westmerciaradiators.co.uk/ca ... rters.html

[Simon Jones]

Brand new for £195: http://www.ebay.co.uk/itm/MAZDA-BONGO-1 ... 1c4fa2555b

[haydn callow]

That's a very good price....

[Simon Jones]

The main body looks slightly shorter than the original part but very good value compared to £100 for a used one which could be well past it's prime: http://www.ebay.co.uk/itm/Mazda-Bongo-V ... 3a84098bb8

[weebrian]

Was quoted £160 supply and fit by MIJ Exhausts who fitted my stainless exhaust system. They manufacture themselves so I'd guess that's a pretty good price.

[JudgeFoozle]

Thanks All,

Will look into those suggestions hopefully at the weekend.

[JudgeFoozle]

Meant to post an update on this in case it helps someone else in future -

The smell of fumes and rough exhaust sound was from some minor damage to the exhaust - whether related to the water dunking or not I don't know. It's been repaired and now all's good.

Glow plugs were replaced - but there was no need. Still plenty life left in the old ones. Same with Rotor arm, leads etc - all still in good condition.

Airbag light still intermittent, but will have this sorted soon.

Thanks again for the input and suggestions.

[mikeWalsall]

I think you mean the spark plugs where replaced .. !!

[JudgeFoozle]

Yep, my mistake!