A hesitant 16
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mat_fenwick
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One method that has worked for me (on my bike) to solve a similar hestitancy problem was to drive for say 30 seconds at 2000-2500 rpm. Then cut the throttle and depress the clutch - preferably near a layby that you can coast to. Then take out a spark plug so you can judge the mixture at that particular rev range.
1993 1.9 TZD Turbo Estate
1996 3.9 V8 Discovery
1993 VW LT35 campervan
1985 Hyundai Stellar V8
2016 Hyundai iLoad
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Ian_Fearn
- Spender lotta cash on Citroens
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I've got what sounds like exactly the same problem Roger with a 1.6 auto with 32k on the clock. Like you say, its difficult to describe but it almost feels like a resonance. Have replaced loads of parts including:
Fuel pump, distributor cap, rotor arm, leads, plugs, cleaned out the fuel tank from under the rear seat, airfilter, carb cleaner/redex and changed the fuel filter.
Have even put 4 new Michelins on it thinking there could be a flat spot on the tyres.
Its definately not a misfire. I'm sure that would really manifest itself under load which its absolutely fine on. Its when you're cruising along at like you say 2500ish rpm and not pushing the throttle hard.
If i was a betting man i'd say the problem is related to the solex carb.
Fuel pump, distributor cap, rotor arm, leads, plugs, cleaned out the fuel tank from under the rear seat, airfilter, carb cleaner/redex and changed the fuel filter.
Have even put 4 new Michelins on it thinking there could be a flat spot on the tyres.
Its definately not a misfire. I'm sure that would really manifest itself under load which its absolutely fine on. Its when you're cruising along at like you say 2500ish rpm and not pushing the throttle hard.
If i was a betting man i'd say the problem is related to the solex carb.
Over and out from me
Sounds like a bit of fuel starvation but at 2500rpm I'm not sure what stage the carb is at. Probably main jet, so it might be partially blocked or even a slightly bunged up emulsion tube maybe. It might be worth stripping it and giving it a good clean and if possible a good blow out with an air line. Carb cleaner is ok but 100psi of air doesn't take any prisoners 
Dave.
2004 C5 Exclusive Estate 2.2hdi automatic.
1990 Bx TGS automatic.
2004 C5 Exclusive Estate 2.2hdi automatic.
1990 Bx TGS automatic.
I had something similar on the DTR Turbo - was the alternator. Regulator had failed and the thing was overcharging intermittently - which produced wipers, lights and indicators working nicely (too well in fact) and some acid on top of the battery due to boiling.
Naturally it was on holiday that I decided to do something about it - and was I glad I didn't take up the shopkeeper's offer of not charging a deposit if I changed the alternator in the road outside his shop!
Naturally it was on holiday that I decided to do something about it - and was I glad I didn't take up the shopkeeper's offer of not charging a deposit if I changed the alternator in the road outside his shop!
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DLM
- Our Trim Guru
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- My Cars: Historically, lots of BX hatches/estates in the 90s/00s - 16/19i/17td/19d
Recent scruffy diesel n/a estate - "The Red Shed" - is no longer mine. - x 9
Something is stirring in the back of my mind about this - I'm sure I experienced the same with at least one of the XU5-engined BXs I owned in the early to mid-90s - and the conclusion was that it was carb-related.
Does the problem occur when the engine is both cold and up to operating temperature? I'd sniff around on the net looking for details of similar problems on ANY XU5-engined cars - particularly the Pug 405.
Does the problem occur when the engine is both cold and up to operating temperature? I'd sniff around on the net looking for details of similar problems on ANY XU5-engined cars - particularly the Pug 405.
Back on two wheels and pedal power for the moment.
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mnde
- Meteor Man
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- My Cars: 2007 Citroen Xsara Picasso 1.6 16V VTX
1982 Citroen GSA Spécial Estate - gone to a new home
1991 Citroen BX16 TGS Meteor - still out there somewhere!
I knew I'd read something about this somewhere. This is from a Autocar roadtest of the new BX16 TRS in September 1983:
"The 16's downdraught Weber carburettor is fitted with an automatic enrichment device which seems to be very effective. Starting is prompt with the engine temperature starting to build within a quarter of a mile of starting from cold. Once warm, though, under hard acceleration our test car exhibited a fairly distinct flat spot in its power delivery, and in common with the BX14 we tested, an occasional hesitance was noted during gentle acceleration at lower engine speeds."
http://www.citroenz.com/BX/rt16.html
Admittedly this is the Weber carb.....
Anyway I agree with demag about carb cleaner. Nothing beats a good strip down and blast with an airline.
Cheers,
Mark.
"The 16's downdraught Weber carburettor is fitted with an automatic enrichment device which seems to be very effective. Starting is prompt with the engine temperature starting to build within a quarter of a mile of starting from cold. Once warm, though, under hard acceleration our test car exhibited a fairly distinct flat spot in its power delivery, and in common with the BX14 we tested, an occasional hesitance was noted during gentle acceleration at lower engine speeds."
http://www.citroenz.com/BX/rt16.html
Admittedly this is the Weber carb.....
Anyway I agree with demag about carb cleaner. Nothing beats a good strip down and blast with an airline.
Cheers,
Mark.
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stuart_hedges
- 1K Away
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mnde
- Meteor Man
- Posts: 1453
- Joined: Tue Oct 18, 2005 5:10 pm
- Location: Aldershot, Hants
- My Cars: 2007 Citroen Xsara Picasso 1.6 16V VTX
1982 Citroen GSA Spécial Estate - gone to a new home
1991 Citroen BX16 TGS Meteor - still out there somewhere!
Hi Roger,
Here's a little collection of threads concerning auto-choke problems. In particular I reproduce the following snippet below.... it may be a good idea to take off the black box on the side of the carb and clean all the linkages with carb cleaner/WD40.
Cheers,
Mark.
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ellevie wrote:
This appears to be from the same source as the pdf link above.
http://www.yaronet.com/posts.php?s=50151
The interesting thing is that it seems to suggest that a sticky choke can be cured by lubricating the waxstat drive rod with a few drops of oil. Might be worth a trying and comparing the before and after required times for the choke flap to reach the full vertical position.
Interesting, because I have done just that and it seems to have done the trick with my autochoke problems!
I took off the body/vacuum chamber and doused the linkages underneath with a liberal helping of WD40 - then I noticed a bit in the Haynes that says to grab the drive rod with pliers and push it into the deflooding capsule as far as possible, then measure the strangler flap opening. By doing this I finally discovered the mechanics of the pull-down system, and also determined that the rod was slightly sticking! As I didn't have much time, I applied more WD and moved the rod in and out several times (I plan to apply a few drops of 3-in-1). But just with this simple fix, the cold starting has improved dramatically and the engine doesn't die suddenly as it was apt to do, even if I held 2000 revs). Hurrah!
Mark.
=================================
Here's a little collection of threads concerning auto-choke problems. In particular I reproduce the following snippet below.... it may be a good idea to take off the black box on the side of the carb and clean all the linkages with carb cleaner/WD40.
Cheers,
Mark.
==================
ellevie wrote:
This appears to be from the same source as the pdf link above.
http://www.yaronet.com/posts.php?s=50151
The interesting thing is that it seems to suggest that a sticky choke can be cured by lubricating the waxstat drive rod with a few drops of oil. Might be worth a trying and comparing the before and after required times for the choke flap to reach the full vertical position.
Interesting, because I have done just that and it seems to have done the trick with my autochoke problems!
I took off the body/vacuum chamber and doused the linkages underneath with a liberal helping of WD40 - then I noticed a bit in the Haynes that says to grab the drive rod with pliers and push it into the deflooding capsule as far as possible, then measure the strangler flap opening. By doing this I finally discovered the mechanics of the pull-down system, and also determined that the rod was slightly sticking! As I didn't have much time, I applied more WD and moved the rod in and out several times (I plan to apply a few drops of 3-in-1). But just with this simple fix, the cold starting has improved dramatically and the engine doesn't die suddenly as it was apt to do, even if I held 2000 revs). Hurrah!
Mark.
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mnde
- Meteor Man
- Posts: 1453
- Joined: Tue Oct 18, 2005 5:10 pm
- Location: Aldershot, Hants
- My Cars: 2007 Citroen Xsara Picasso 1.6 16V VTX
1982 Citroen GSA Spécial Estate - gone to a new home
1991 Citroen BX16 TGS Meteor - still out there somewhere!
Slightly different symptoms on my car, but again reproduced from another thread:
http://bxclub.co.uk/forum/viewtopic.php?t=5243&start=0
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Mine used to stutter if I tried to accelerate too fast in town in 2nd/3rd. I'd try what I did: unscrew the black box off the side of the carb, spray all the linkages behind with carb cleaner, re-oil them all and lubricate the choke pull-down drive rod which is at the bottom left of the autochoke chamber. Grab the rod with needle-nose pliers and push it leftwards a couple of times - it should move freely and spring back when you let go. Since I did this simple thing, I've had no cutting out whatsoever under heavy acceleration and the car feels somewhat more powerful. I assume that the sticking drive rod was causing an over-rich mixture for normal operating temperatures.
Regards,
Mark.
http://bxclub.co.uk/forum/viewtopic.php?t=5243&start=0
=====================
Mine used to stutter if I tried to accelerate too fast in town in 2nd/3rd. I'd try what I did: unscrew the black box off the side of the carb, spray all the linkages behind with carb cleaner, re-oil them all and lubricate the choke pull-down drive rod which is at the bottom left of the autochoke chamber. Grab the rod with needle-nose pliers and push it leftwards a couple of times - it should move freely and spring back when you let go. Since I did this simple thing, I've had no cutting out whatsoever under heavy acceleration and the car feels somewhat more powerful. I assume that the sticking drive rod was causing an over-rich mixture for normal operating temperatures.
Regards,
Mark.