Engine maybe a bit slow to start
Discussion
65-reg Suzuki Swift Sport 1.6, done 35k.
It seems a bit slow to start recently. What do you think?
Short clip here:
https://www.youtube.com/watch?v=_XDzvR9dH50
It seems a bit slow to start recently. What do you think?
Short clip here:
https://www.youtube.com/watch?v=_XDzvR9dH50
Bullet-Proof_Biscuit said:
Sorry can't watch the vid but- cranks longer than it used to before it catches? New spark plugs....
Thanks, spark plugs (or coils) are near the top of my list.Being a bit slow to start happens regardless of whether the engine is cold or at normal temperature after a long run.
I also wonder whether it's either not burning properly (plugs/coils) or running a bit too rich because I just noticed the tailpipe exits seem to have gathered a fair bit of powdery-like carbon.
trickywoo said:
What MPG are you getting out of it?
MPG doesn't seem to have noticeably changed in recent days/weeks and isn't hugely off from figures on sites such as Honest John's real mpg.Around town it gives about 40mpg and similar on the motorway. On single-carriageway roads it's about 50mpg.
Surprisingly, the trip computer is accurate.
Coincidently I've been thinking my 13 plate Sport has been a bit slow to start recently. It doesn't seem to crank sluggishly, but just takes a little longer than expected to catch.
Very likely the battery is simply getting a little tired since it's now almost 5 years old (though the battery in my EP3 Civic lasted well over double that!). I fitted a new set of the correct (expensive) Iridium plugs a few thousand miles back, so doubt that is the issue in my case.
Very likely the battery is simply getting a little tired since it's now almost 5 years old (though the battery in my EP3 Civic lasted well over double that!). I fitted a new set of the correct (expensive) Iridium plugs a few thousand miles back, so doubt that is the issue in my case.
Mr2Mike said:
Coincidently I've been thinking my 13 plate Sport has been a bit slow to start recently. It doesn't seem to crank sluggishly, but just takes a little longer than expected to catch.
Very likely the battery is simply getting a little tired since it's now almost 5 years old (though the battery in my EP3 Civic lasted well over double that!). I fitted a new set of the correct (expensive) Iridium plugs a few thousand miles back, so doubt that is the issue in my case.
Thanks. Interesting that you have a similar problem.Very likely the battery is simply getting a little tired since it's now almost 5 years old (though the battery in my EP3 Civic lasted well over double that!). I fitted a new set of the correct (expensive) Iridium plugs a few thousand miles back, so doubt that is the issue in my case.
How many miles had your plugs done? What type of use? What condition were they in when you took them out?
I bought the car with 26.5k on it and performed a full service at 28k. The old plugs looked absolutely fine, no obvious wear and typical lean looking colour that you always seem to get on modern cars. They could likely have been left in for another 28k, but changed them anyway. Cant really say what use the previous owner gave it, but I do about 60 miles per day commuting in it.
The car did have a funny turn some months ago where it cranked for ages, maybe 5-6 seconds or so before firing but its never done it since.
Never had a code reader on it so will do that this weekend, just in case. My wifes Octavia suffered from a dead cam sensor, and one of the symptoms was extra cranking before it would start.
The car did have a funny turn some months ago where it cranked for ages, maybe 5-6 seconds or so before firing but its never done it since.
Never had a code reader on it so will do that this weekend, just in case. My wifes Octavia suffered from a dead cam sensor, and one of the symptoms was extra cranking before it would start.
Edited by Mr2Mike on Friday 8th June 23:24
Mr2Mike said:
...... My wifes Octavia suffered from a dead cam sensor, and one of the symptoms was extra cranking before it would start.
What other symptoms were there?Immediately upon starting the engine, sometimes the rpms settle at ~1500 for maybe up to 30s before then dropping to ~1000.
At other times the rpms just settle at ~1000.
There's no obvious way to predict whether it will do the fast idle.
When warm, idle rpms are 500-600, such as when sitting in a queue of traffic.
Yes, it has idled high after a start before, though I don't remember if that happened after the extended crank incident.
It also idles very low when the engine is fully warmed, like ~500 RPM which actually causes a bit of vibration in the car. This seems to be very commonly reported though, I guess Suzuki didn't want for the added weight and expense of Stop/Start so tried the next best thing...almost stopped
It also idles very low when the engine is fully warmed, like ~500 RPM which actually causes a bit of vibration in the car. This seems to be very commonly reported though, I guess Suzuki didn't want for the added weight and expense of Stop/Start so tried the next best thing...almost stopped
Mr2Mike said:
Yes, it has idled high after a start before, though I don't remember if that happened after the extended crank incident.
It also idles very low when the engine is fully warmed, like ~500 RPM which actually causes a bit of vibration in the car. This seems to be very commonly reported though, I guess Suzuki didn't want for the added weight and expense of Stop/Start so tried the next best thing...almost stopped
To overcome that annoying idle problem a simple circuit will solve it, the below circuit uses the manufacturers temp sensor resistance for starting and switches over to a customer selected resistance range when the engine is running, the thing is the resistance needs to make a very small adjustment so as not to mess up throughout the engines RPM rangeIt also idles very low when the engine is fully warmed, like ~500 RPM which actually causes a bit of vibration in the car. This seems to be very commonly reported though, I guess Suzuki didn't want for the added weight and expense of Stop/Start so tried the next best thing...almost stopped
Obviously a different temp sensor may do the job but they are often difficult to obtain with the correct required range of resistance
A on/off temp sensor may be needed to switch the resistor in and out so that it only works when the engine is fully warmed up, this job could very likely be done without the relay, perhaps a temp switch and resistor will solve the problem depending upon whether the resistance needs to be highered or lowered at tickover when the engine is warm, obviously a temperature switch will only be able to switch a resistor in parallel with the engines original temp sensor
The relay circuit may also need modifying for series or parallel switching
Edited by Penelope Stopit on Saturday 9th June 11:10
Bullet-Proof_Biscuit said:
Trust me try new spark plugs first, you’ll be surprised.
Though you mention coil? Is this vehicle old? Does it have points? They’ll want adjusting more frequently than plug replacement!
Pretty much all petrol engines have an ignition coil. Points haven't been fitted to cars in the last ~40 years.Though you mention coil? Is this vehicle old? Does it have points? They’ll want adjusting more frequently than plug replacement!
The Swift uses long life Iridium plugs that they advise be changed at 36,000 miles. I personally don't think that plugs have anything to do with this since it's not as though it's even trying to start, it just cranks for a slightly longer period then immediately catches and starts. It feels more like an ECU/sensor issue to me.
I expect it'll have some sort of idle air control valve to control the idle speed. It's quite common for these to get gummed up over time and stick in the wrong position, which can cause the idle speed to vary unexpectedly. Particularly if the idle speed is sometimes too high, that would be my first suspicion. I'm not familiar with that engine so I can't tell you where it is but these are usually on the inlet manifold in the vicinity of the throttle body and quite easy to get to for cleaning.
I wouldn't recommend frigging the coolant temp sensor to try to trick the ECU into raising the idle speed. If the engine is working properly, that would also bring in cold enrichment. If it isn't, better to correct the underlying problem rather than try to counteract the symptoms.
I wouldn't recommend frigging the coolant temp sensor to try to trick the ECU into raising the idle speed. If the engine is working properly, that would also bring in cold enrichment. If it isn't, better to correct the underlying problem rather than try to counteract the symptoms.
I don't know about the Suzuki Swift in particular but many modern petrol cars have Secondary Air Injection (SAI) that is activated on start up when certain parameters are met and when this pump is running the idle speed is normally increased. It's purpose is to speed up the process of getting the cats up to their operating temperature.
Gassing Station | Engines & Drivetrain | Top of Page | What's New | My Stuff