Technical Car/Motor Issues > Daewoo Espero - 97 2.0 Hesitancy
Thread Author: Stuu Replies: 16

 Daewoo Espero - 97 2.0 Hesitancy - Stuu
Not a serious thing but it niggles more than anything.

On low throttle openings my car seems to labour between idle and 1800 rpm but then on the same throttle opening, at 1800 rpm it suddenly 'wakes up'. This is especially noticeable in 2nd gear and to a lesser extent in 3rd, such as when pulling into side roads.

If I give it more juice its fine and you dont notice any jump in power, but if your trickling around suburban streets, it annoys a little.

My first thought was it was a fuel issue - its got worse since I stuck the Redex through and I wondered if maybe the fuel filter was maybe past its best?

I just seemed odd that it always happens at exactly the same revs each time. Its not misfiring that I can hear and all the plugs were cleaned and gapped a few thousand miles ago.
I figured if it was air supply, that would be a problem on bigger throttle openings rather than light ones.

Any clues?

 Daewoo Espero - 97 2.0 Hesitancy - madf
?Gummed up throttle (Redex made it worse by shifting some deposits a little).

Take off air filter (? clean) and look.

Toothbrush and carb cleaner job.. plus lots of heavy duty tissues or rags which do not leave deposits in inlet..

30 mins job for a man of your calibre...:-)
 Daewoo Espero - 97 2.0 Hesitancy - Dog
Check out all the rubber vacuum pipes for leaks.

 Daewoo Espero - 97 2.0 Hesitancy - Stuu
Vacuum pipes - I know they exist, but how do I identify them in the spahetti junction that is under the bonnet?
I fondly recall my Reliant which had just three rubber hoses under the bonnet! Even I knew what I was looking at!
 Daewoo Espero - 97 2.0 Hesitancy - Dog
>>how do I identify them in the spahetti junction that is under the bonnet? <<

Yeah, that's the trouble with the post mrk 2 Escort era :)
You'd have to remove the air filter to check out all the black rubber vac hoses, but there will be vac hoses attached to that as well so if you didn't feel competent about doing that, I'd leave well alone!
A blocked fuel filter would more likely cause fuel starvation under load and at higher speed,
You say the addition of Redex seemed to make it worse so that may have cleaned up some air bleeds further weakening the air/fuel mix, but I'm stabbing in the dark really and without seeing the critter it could be any number of things really, haven't any of your customers got any of the old Sun/Crypton type scope based engine analysers gathering dust in the corner somewhere.
 Daewoo Espero - 97 2.0 Hesitancy - Stuu
Right, I did something and it made a difference.

Basically, I gave the back box a couple of stiff punts with my boot. Hesitancy almost disappeared immediately.
Now I have no idea what an internally failing backbox would do to the running of the car, but given that its quite an old 'box and when the middle exhaust section was replaced, it needed quite alot of persuasion with a hammer to part that and the back box from eachother, could this be the root of the problem?
 Daewoo Espero - 97 2.0 Hesitancy - Zero
It could be blocked, and you freed it up a bit?
 Daewoo Espero - 97 2.0 Hesitancy - bathtub tom
When I had a blocked back-box the symptoms were a lack of grunt a higher revs - it wouldn't go to 7K no more and a quiet 'woosh' at tick-over instead of a definite pap, pap, pap.

I went 'fishing' in it with a bit of wire bent into a hook at the end and eventually removed all the wadding.

tinyurl.com/y8qk29v
 Daewoo Espero - 97 2.0 Hesitancy - swiss tony
>> Now I have no idea what an internally failing backbox would do to the running
>> of the car

Try breathing through a loo roll centre.

now pack out that loo roll centre with other loo roll centres..... now try and breath through it.

That's what happens as the baffles clog up the silencer!

(or think of clogged artery's ....)

 Daewoo Espero - 97 2.0 Hesitancy - Stuu
I noticed a bit of fluffing coming from this bit on my exhaust:

i234.photobucket.com/albums/ee119/stunorthants/The%20Korean%20Expresso/SDC10393.jpg

Im guessing its one end of the CAT, does it look right? Its where the noise is coming from, that Im certain. Looks like ill be replacing the entire system at this rate...
 Daewoo Espero - 97 2.0 Hesitancy - Zero
It looks to be hanging down a bit, its at a funny angle.
That joint looks knackered.
 Daewoo Espero - 97 2.0 Hesitancy - Stuu
I did think that, but a 2nd or 3rd opinion always good. Im hoping its not massively expensive, can only hope, perhaps in vain!
 Daewoo Espero - 97 2.0 Hesitancy - VxFan
>> Im guessing its one end of the CAT

Front pipe (the part between the manifold and cat) according the quick google search I just did.

www.onlineautomotive.co.uk/Products.aspx?CategoryID=114078

www.onlineautomotive.co.uk/ProductImages/301298.jpg

£28.14 ex VAT.

Another image from Bosal - tinyurl.com/2bu5b53
 Daewoo Espero - 97 2.0 Hesitancy - Stuu
Thats great, thanks. So looking at it, if its sagging like that and its one part, its split at the join ive pictured then?
I better check where the hangers are as I dont want that splitting and hitting the ground.

Could this be why the cars been so hesitant?

 Daewoo Espero - 97 2.0 Hesitancy - VxFan
>> Could this be why the cars been so hesitant?

Maybe, especially if it's leaking as you will have lost back pressure in the system. As it's so cold you should be able to see steam coming out the joint if it's leaking. You can highlight this further by getting someone to block the tailpipe by covering it with a rag and their hand.
 Daewoo Espero - 97 2.0 Hesitancy - Zero

>> Could this be why the cars been so hesitant?

Entirely possible, lack of back pressure and the lambda sensor could be getting a false reading.

Looking at that, it looks like its taken a knock, possibly exhaust pipe reversed into something?
 Daewoo Espero - 97 2.0 Hesitancy - Stuu
There is a country road out on one of the country estates I do work on whos roads havent been done in many years, the sides of the road have sunk, leaving a raised middle.
There are also some bumps which pitch the car about and I know maybe once or twice when I didnt slow right down, it has clonked a couple of times when ive had the car loaded up.
Its the only time its hit while ive had it so prob that OR it was like that before and hits because its sagging. Either way, better sell the family silver :-)
Latest Forum Posts