![]() | #31 |
Distinguished - BHPian Join Date: Apr 2013 Location: Beans Town
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| Re: Engine knocking, hesitation and performance issues If it was me I'd show it to the HSS immediately as they would go in detail about the prev owners running history. Sure sometimes they suggest early replacement/unnecessary jobs but that's where the customer has to intervene and ask more questions. Timing belt change is recommended now due to the age and mileage of the vehicle, the new one will last the remainder of your ownership easily so why risk engine damage. Tell the HSS to give a thorough cleaning of injectors & throttle body, decarbonizing, check spark plugs and V-belt condition. Also use Sys G fuel additive annually and ensure the fuel is of good quality. This should stop/reduce knocking, if it doesn't then only should the engine be looked at. Knocking is a small symptom of some underlying mechanical fault, so the guy who rubbished it off seems to want to make his buck on overhauling. The PS fluid is also due for change. Simple solution > HSS. |
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![]() | #32 | |
BHPian ![]() Join Date: Nov 2011 Location: Bangalore
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| Re: Engine knocking, hesitation and performance issues Quote:
Also, my car returns just 10-11 kmpl! ![]() Mod Note : Please quote ONLY the relevant bits of a post. Quoting a full, long post inconveniences our mobile readers. Thanks! Last edited by Aditya : 14th April 2014 at 17:06. | |
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![]() | #33 | |
Senior - BHPian ![]() | Re: Engine knocking, hesitation and performance issues Quote:
You have kind of answered your question yourself. A car on low fuel has a fair good chance of sucking in all the dirt and grime from the fuel tank, which is usually settled down. Get all your injectors cleaned, replace the fuel filter and clean your throttle body. You should be up an running. A simple bottle of system G should bring in a marked difference. Try that first. Pramod | |
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The following BHPian Thanks pramodkumar for this useful post: | wooka |
![]() | #34 |
Distinguished - BHPian ![]() | Re: Engine knocking, hesitation and performance issues Glad to see various members offering enthusiastic advise. However, if I were you I would never just start swapping bits or having any work carried out until a competent engineer/mechanic has done some prober diagnostic analysis. First, and I really can't judge that, is it real engine knocking you hear. Either, you have heard if before and you know what it is, or your mechanic has confirmed. Its often described as pinging sound. When you press on the accelerator it becomes more pronounced. Typically at idle or low loads its not or less present. Rings a bell?? When you switch off your engine, does it stop immediately or rattles on a bit? If it is knocking, there are actually several different types of engine knock, but lets keep it simple, check here : http://en.wikipedia.org/wiki/Engine_knocking Your car is likely to be equipped with an OBD port, so get it hooked up and see if there are any codes. Has your car a OBD and if so, did they hook it up and saw any codes? The most simple causes for engine knock are: - Wrong fuel If you're using a fuel with a lower octane number then the recommended number you might be encountering engine knock. The solution is very simple, put the proper fuel in! - Incorrect spark timing I'm not familiar with your car, again, the easiest is to check this via OBD read out, and if not you just need to check the settings manually. Check spark plugs too. If it is anything to do with the ignition, its more likely to be the timing than the plugs, but plugs are checked very easily, so you might as well - Carbon deposits built up in the cylinder A well equipped workshop should be able to take a little peek in your cylinders to see if there is carbon deposit built up using a simple endoscope. I don't understand why your mechanic would want to change the time belt or open up the engine head as part of this problem. If it is part of the normal preventive maintenance thats fine, of course. Your owners manual should tell you when it needs changing. If he suspects the timing belt to be the culprit of the knocking he should be able to clearly measure this. It would have to be pretty loose, or mounted incorrectly to start with in the first place to get the engine to knock. He should be able to measure that easily. Opening up of the cylinder head, no of course not, find a workshop that invested a couple of hundred bucks in a tool (endoscope) to look into the cylinder! I have one, and I'm just an amateur. Clean out the throttle body?? Why would you do that or give such advise? First, just look inside the throttle body, and when its is dirty decide on an appropriate course of action. So, the advice offered by our esteemed members as well as your mechanic seems to be void of any logical and or analytical approach, i.e. just hit and miss. Or perhaps more appropriate call it replace and see what happens. Admittedly, that might get rid of your problem. I am of a somewhat more cautious disposition and I want to understand what is going wrong first before I start opening up stuff, or replacing it. Good luck, Jeroen |
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![]() | #35 | |
Senior - BHPian ![]() Join Date: Aug 2005 Location: New Delhi
Posts: 1,422
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| Re: Engine knocking, hesitation and performance issues Quote:
Check your air filter - is it too dirty - if so , replace? Are there any obstructions in the inlet manifold? Is the ignition timing off? Ask your mechanic to check TDC using a strobe. Is the coolant level okay? | |
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The following BHPian Thanks joybhowmik for this useful post: | wooka |
![]() | #36 | |
Distinguished - BHPian ![]() | Re: Engine knocking, hesitation and performance issues Quote:
Just to add: The TDC, Top Dead Center is a given and is fixed. Checking it won't do anything, what I assume you mean is similar to what I suggested, is to check the ignition timing, which is measured against the TDC. Your engine ignition needs a certain advance and that advance is also dependent on RPM and engine loading. You can do a few basic checks with a strobe. So you check the ignition advance against the TDC. Better yet, if the car has OBD port, get it plugged into a proper, preferably manufacturer specific OBD analyzer. Jeroen | |
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![]() | #37 |
Senior - BHPian ![]() Join Date: Aug 2011 Location: Boston
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| Is the knocking sound heard only at certain RPMs in all the gears? I faced the issue of engine knocking sound at 1200 rpm in all the gears in my i20 crdi. It was more prominent in the 1st and 2nd gear. First the HSS guys just reset the injector codes in ECU but the issue appeared again. Then they cleaned the diesel tank, fuel lines and the injectors after which the issue disappeared. Last edited by guyfrmblr : 14th April 2014 at 17:20. |
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The following BHPian Thanks guyfrmblr for this useful post: | wooka |
![]() | #38 | |
Senior - BHPian ![]() Join Date: Nov 2011 Location: Chennai
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| Re: Engine knocking & hesitation Where is my post asking wooka to check for DTCs and whether the O2 sensor is causing the problem of hesitation and lurching (by unplugging it)? Where did it go? ![]() It seems to have vanished into thin air ![]() Quote:
Last edited by RSR : 14th April 2014 at 18:20. | |
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The following BHPian Thanks RSR for this useful post: | wooka |
![]() | #39 | ||||||||
BHPian ![]() | Re: Engine knocking, hesitation and performance issues Points I need to iterate after going through the posts: 1. I have changed spark plugs and the problem is as before I began troubleshooting. 2. Just used an injector cleaning solution in the tank ( 1 bottle of ABRO injector clean) and have burned twenty litres since then. No difference. 3. I've been using System-G for 3 months now and the lurching at cold start won't improve. I do about 600~1K KMs a month so System G has had plenty of time to work. 4. The timing belt change interval is at 90K I believe. @ 75K I'm not that off. I understand the belt must really be loose for it to cause knocking. 5. The knocking is indeed a pinging sort of sound. Think a diesel engine's noise but more erratic, over the regular petrol engine noise. 6. The mechanic said this is minor but I can clearly make a distinction as the situation deteriorates, and I've made this observation over a few months. 7. If the low fuel caused guck to get sucked up into the system, do I need to get fuel lines and the tank cleaned, fuel filter changed? I thought the fuel filter kept the injectors clean! Quote:
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O2 sensor.. is this the one at the exhaust manifold? I do not have any idea where to look, honestly. In case this is out, what are my options? Sorry you lost your post. Thanks for working another one! Though I wonder how this would affect a cold engine against a warm one. There's no problem in gear, just as I enter one. There has been some idling engine RMP variation over the past few months. The RPM is up as of today, was lower a few months back prior to the last service. ---------------------------------------------- I'm going to thank everyone for their posts. Very good stuff here and I'll have the HSS guys run their tests against my checklist. I'm making a little checklist. Please just highlight the point number and approve if need be. I really don't want anyone to have to write the same stuff over and again for one car ![]() Checklist: 1. IgnitionCheck ignition timing @ HSS as no one else seems to know any better here. This is against the TDC I understand ![]() 2. InjectorsTest injector spray pattern and volume @ HSS? 3. Fuel linesClean out- fuel lines @ an outside workshop. Change fuel filter? (it's been 14K since the last change) 4. CylindersGet the cylinders opened and see if they need work ( decarb etc.) Will get this done outside @ a workshop. 5. Timing beltTiming belt needs changing anyway. Can't afford a snap. 6. Throttle body cleaning on inspection.OEM Santro belt @ Rs.800 and the rest labor. 7. OctaneI'll add some reagent grade acetone to top the octane and see if it helps. This would be indicative of an unusually high compression ratio and either the mixture of fuel+ air is lean or carbon has reduced available room in the cylinder.I have a bottle lying so that's OK. Have used it for 3-4 months and soon after I discontinued the problems came up. Coincidence? 8. O2 sensorGet the O2 sensor checked and ODB readings for some stats. Will post stats with tBHP as I get them. Please feel free to contribute. ![]() | ||||||||
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![]() | #40 | |
Senior - BHPian ![]() Join Date: Nov 2011 Location: Chennai
Posts: 1,803
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| Re: Engine knocking, hesitation and performance issues Quote:
Yes, the O2 sensor is the one just after the exhaust manifold. This is the one that usually goes bad or gets clogged. In addition to this, your car may have another O2 sensor just after the catalytic converter, depending on the emission norms it was designed for. There is no need to remove the sensor to test it. It will have a plug, just unplug it and drive the car to see if the hesitation and lurching forward persist. If it doesn't happen, the O2 sensor is the culprit. It would be similar to this: ![]() If it has gone bad, it needs to be replaced. It can cost up to 7k rupees at a Hyundai workshop, but you can source a genuine part outside for cheaper, if you know the part details. If you're lucky, it may just be clogged. In this case, a careful cleaning will restore it's functionality. Of course, this is just a possibility that needs to be checked by unplugging it first. It happened on our i10 iRDE which has the same 1086cc engine. Last edited by RSR : 15th April 2014 at 10:28. | |
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![]() | #41 | ||||||
Senior - BHPian ![]() Join Date: Aug 2005 Location: New Delhi
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| Re: Engine knocking, hesitation and performance issues Quote:
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This is not something that needs a whole lot of specialised equipment (see this )- so you can get it done at a trusted mechanic. At least you will get much better skills working on the car. Quote:
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Decarbonization is overrated and oversold. However, it's your choice - but do consider this thread before electing for open heart surgery on this account. Quote:
Mandatory replacement of camshaft timing belt @ 80 K km or multiples thereof. Under special conditions (see list below) - replace the timing belt @ 60 K km or multiples thereof. a) Driving in areas using salt or other corrosive materials or in very cold weather b) Driving in sandy areas c) More than 50% driving in heavy city traffic during hot weather above 42șC d) Driving in mountainous areas. I don't know if you have specific evidence of the timing belt having cracks on it, but if not - why change out something that works? But if you still decide to go ahead and do so, ensure to change out the belt tensioner as well. Quote:
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The following BHPian Thanks joybhowmik for this useful post: | wooka |
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![]() | #42 | ||
BHPian ![]() | Re: Engine knocking, hesitation and performance issues Regarding the O2 sensors, Was hoping to find something here so I've made a post, though if anyone can tell me what to look for voltage and part wise I'd be thankful. Don't want to be conned! Also any way I can get this adjusted/cleaned? I noticed increased idle RPMs post service ( in front of me so I don't think any sensors were touched) and a guy said the O2 sensor might need cleaning. goo.gl/wm4Nvc Quote:
I'm going point by point here. 1. I'll try to get this done but I'll have a hard time looking for help. Anywhere I can buy the endoscope online? 2. Decarb: I'm going to do this only if the compression ratio has gone up. Can this be scanned through OBD or some alternate method? 3. Any clue how much this should cost @ 3rd party workshops? The belt is for Rs.800 OG Hyundai , and the tensioner, i have no clue, apart from labor. 4. Quantity of acetone used was 1-1.5ml\L of fuel. So thats about .1 to .15 % dilution. I don't think that's a problem as it was used as a fuel additive in Vietnam @ much higher concentrations to increase FE and clean engine parts. However, cheap rubber seals on bikes gave out and resulted in it being discontinued. If anything it's supposed to decrease surface tension, up octane( nothing significant at my usage levels) and clean fuel lines and injectors I believe. Quote:
1. No Diag lights so far. Bulbs are working fine. 2. The one after the cat con will also need to be checked, right? 3. Unplugging will make the O2 sensor read lean? So the mix will get richer and cooler and not knock. This is definitely going to fix it, right? Since I believe the ECM will try to maintain a 50% lean \ rich mixture ratio. I could be wrong, and probably am, please correct me here. ![]() 4. 7K ![]() ![]() 5. Clogged would be loaded with carbon? If so, an ultrasonic or chemical bath/ abrasives -- which is the best way out? 6. Thanks for sharing and helping a nuble out. | ||
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![]() | #43 | ||||
Senior - BHPian ![]() Join Date: Aug 2005 Location: New Delhi
Posts: 1,422
Thanked: 2,297 Times
| Re: Engine knocking, hesitation and performance issues Quote:
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Get a compression test, cylinder leak down test and a power balance test done to pinpoint the problem. See this video of a See this video of a See this video of a Quote:
Cost of Hyundai genuine timing belt: Rs 800/- Cost of Hyundai genuine tensioner : Rs 550/- Labour cost : Rs 100/- Though mind you - I could have waited for another month or so.... Quote:
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The following BHPian Thanks joybhowmik for this useful post: | wooka |
![]() | #44 |
BHPian ![]() | Re: Engine knocking & hesitation Thanks joybhowmik, Will wait till thursday, my trip to the mech, and will post back. Still, for the O2 sensors, what voltage range am I looking at, and how can they possibly be cleaned? |
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![]() | #45 |
Senior - BHPian ![]() Join Date: Aug 2005 Location: New Delhi
Posts: 1,422
Thanked: 2,297 Times
| Re: Engine knocking & hesitation
An O2 sensor issue, would show up in the OBD scan. There is a range of O2 sensor codes, so ensure to get the scan done on a dedicated scanner, and have the mechanic refer the service manual for the meaning. |
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