Motorway sluggishness

Hey there,

today I was driving north on the A1 from Leeds to Durham. When I got to the 50mph limit I slowed down and sat behind a lorry. At one point I put my foot down (50mph, 5th gear) to get the speed up for an upcoming hill, but instead of slowly surging power like usual, the car started shaking and bumping back and forward with a quick frequency; it felt like the car had no power at all. This lack of power continued for a minute or so and I couldn't get any speed up, then it went away as soon as it began and I drove on as usual.

I've had idle trouble and its been stalling at traffic lights in neutral lately, do you think that's related? Also it was really REALLY windy today, but I couldn't see how that would cause it, unless somehow I was caught in a magical wind trap behind the truck.

The car's a 1993 3.5 v8i

Cheers for any help.

Hi, it would be good to know what engine it is

sierrafery said:

Hi, it would be good to know what engine it is

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haha yeah I realised that, just changed it

(3.5 v8i by the way)

Tubes63 said:

Hey there,

today I was driving north on the A1 from Leeds to Durham. When I got to the 50mph limit I slowed down and sat behind a lorry. At one point I put my foot down (50mph, 5th gear) to get the speed up for an upcoming hill, but instead of slowly surging power like usual, the car started shaking and bumping back and forward with a quick frequency; it felt like the car had no power at all. This lack of power continued for a minute or so and I couldn't get any speed up, then it went away as soon as it began and I drove on as usual.

I've had idle trouble and its been stalling at traffic lights in neutral lately, do you think that's related? Also it was really REALLY windy today, but I couldn't see how that would cause it, unless somehow I was caught in a magical wind trap behind the truck.

The car's a 1993 3.5 v8i

Cheers for any help.

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It happens cleaning the crankcase breathers and a bottle of injection cleaner works for me.

discool said:

It happens cleaning the crankcase breathers and a bottle of injection cleaner works for me.

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It's common is it? Bloody annoying, I'll tell you what haha. I'll try the injection cleaning before getting at the crankcase haha

Should probably also mention that the fuel economy has dropped a little bit lately.

Cheers

I always start simple (that's about as much as I can manage normally) I'd try fuel filter and air filter first as well as what discool said and see if that helps.

Tubes63 said:

It's common is it? Bloody annoying, I'll tell you what haha. I'll try the injection cleaning before getting at the crankcase haha

Should probably also mention that the fuel economy has dropped a little bit lately.

Cheers

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Maybe thats because your pressing harder on the pedal to overcome your probs.
The breather is the round unit on the rocker cover with a hose from the top going to the plenum, both can coak up if left untouched

And YES air/fuel filter 'nice one barmatt' as I always for get about them.

Ok cheers guys, I'll get on it!

sounds like it could be the coil or HT leads breaking down under load-try looking under the bonnet at night with engine running to see if you can see any sparks anywhere-when really bad its like a thunder storm-if you have a distributor cap,look inside for "tracking lines" grounding to earth,assuming cap is not cracked,if so replace it

OK I checked the air filter - looks a little dirty but nothing out of the ordinary, only been in about 8 months, so I dusted that off a bit. I also added injector cleaner to the petrol... and topped up the oil (which was low ). This appeared to help a bit but it was still idling badly.

I just checked the crankcase breather filter...:
a) it was only loosely screwed in - as soon as I touched it it was wobbling
b) it was very dirty, I don't know how black and oily it SHOULD look, but mine looks like this:
c) there was and still is NO O-ring... Haynes says there should be, so should there be?
d) there was a fair bit of gritty dirt on the inside of the hose, but no blockage.

I want to clean it, but just want to make sure degreaser will be ok. Haynes says petrol I think but that sounds like an expensive way to clean a filter...

I don't think there are any problems with the electrics but I'll check in a minute. The HT leads are pretty much brand new.

Cheers guys

Geoff

That breather looks ok. Obviously a clean is good but It looks like mine does now. When mine was blocked it was like there was like someone had left a BBQ in there. Blow through it from pipe end, if it's anything more than no resistance then consider it blocked. Should be like blowing through a hula hoop!

It should have an o ring yes, mine does at least. Bit of insulating tape on threads will be enough to seal that though. Ptfe better!

So rinse it out anyway, degreaser is fine. Also check the big pipe (you said you had) but also check the t piece that's fitted to it, and the smaller pipe that comes off. This small pipe is fed from the big pile through the T which has a brass restrictor in it, so there is about 1mm hole. Check this whole T piece is clear especially the small hole, check the plenum fitting is clear, mine was gummed up and nearly blocked too.

Idle is difficult to control on this old engine anyway, more so if pipes are blocked up. Check idle valve at back of plenum and associated pipes.

Worth checking your vehicle speed sensor is working ok, although when this fails it usually causes stalling when you come to a stop, not when sat at idle.

Basically engine cleanup and tune up mate, check ignition timing, check mixture trim on airflow meter. Lots of things to keep in shape.

She'll be sweet again soon enough

Righto, sounds like a plan. The idle has always been a little bit funny...

I'll get on it either later tonight or tomorrow and let you know. I did have a look at the t-piece quickly but didn't take all the pipes off.

Thanks noisy,

Yeah no worries pal, just be systematic.

Oh and btw, your signature gives me lols

Mr Noisy said:

Yeah no worries pal, just be systematic.

Oh and btw, your signature gives me lols

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haha yeah I have it as a bumper sticker... Get nasty looks from people in Priuses but whatever

Your breather looks gummed up to me you should be able to see through the gauze which is just as an oil strainer/barrier it is not a filter, so just wash the the can and hose in petrol as it soon dries.
If the filter doesn't clean up replace it, it is a service item and changed at a 12,000 service by LR dealers and it comes with a large O ring.

If you looking for things to do you could also check your base idle.

Ok I'll try cleaning it up. Not sure about the base idle though!

Fair point discool I did take mine out the other day and remember being able to see daylight through it.

Tubes, you can pull the gauze out, clean it properly, and then stuff it back in. No need to replace IMO, it's a simple device. I did this ages ago, I forget but it must have been bad. Whole rocker covers were full of black pudding.

Told you some kids had been having a barbecue in there!

Mr Noisy said:

Fair point discool I did take mine out the other day and remember being able to see daylight through it.

Tubes, you can pull the gauze out, clean it properly, and then stuff it back in. No need to replace IMO, it's a simple device. I did this ages ago, I forget but it must have been bad. Whole rocker covers were full of black pudding.

Told you some kids had been having a barbecue in there!

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Ah ok... I had another look just now and could see daylight but only a glimmer and only when I held it up against a bright light haha. So I'll do that asap.

Have to say though, just took the car out for a twenty minute drive around town... Didn't miss a beat, not stalling or bad idling or anything. First time i've had a drive in a long time without having to "heel-toe" the brake pedal/accelerator. So something in this playing has possibly fixed the problem...?

All I've done is put that injector cleaner in the fuel, top up the oil and blown through that crankcase breather system. It's either fixed or one of those annoying "come and go" problems.

Cheers guys, I'll keep you posted. I'll still clean out and replace filters and what not.

They seem happier when cold in my opinion. It's when things get warmed up that problems tend to develop (usually).

Probably because the mixture is much less precisely set when cold.

It can often be a combination of niggling issues - a blocked breather, dirty injectors, a loose connector here etc. As everyone has said, do the little things first. How old are the Dizzy cap, rotor arm and leads? If you don't know, replace them and buy the best you can afford. Get magnecor KV85 leads. On most cars they're overkill but the V8 has such a length to cover and so often gets wet that that little bit of extra insulation works wonders in damp conditions. They're almost essential if you're running LPG.
Prius drivers give everyone dirty looks, maybe it's because someone has told them their damn pious mobiles are full of rare earth metals and are far worse for the planet than that old Disco that trundled past made of nothing but iron and aluminium ore and paid it's production pollution debt years ago....