Replaced a timing belt and timing belt tensioner pulley. Still wont run. Why?
My timing belt snapped. And i replaced it. I also wound up replacing the timing belt tensioner pulley. I put t all back together and the car sputters as if it wants to start. The wires and everything are good. And i have fuel pressure. But it sounds like it wants to start. Any idea why?
My car has 197000 miles.
My car has an automatic transmission.
Experienced mechanics share their insights in answering this question :
If you broke the timing belt while driving then you may have bent the valves. You should have the engine compression checked to see if you are loosing compression due to bent valves. If compression is low then have cylinders leak tested to see which cylinder is leaking and what valves are bent.
How to Identify and Fix Common car Problems ?
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The most common causes of timing belt tensioner failure include: Wear and tear: On a new mechanical timing belt tensioner system, the timing belt tensioner spring is wound tightly by two tension rods. Over time, the spring stretches out and loses its tension. As a result, the entire tensioner becomes too weak.
When the timing belt is replaced, other parts, including the tensioner, should be replaced at the same time. This is because these components wear out at essentially the same rate as the belt. For instance, the tensioner bearings could dry out or even seize.
For some vehicles, you may be able to check the timing belt tension with a smartphone. When the belt is tight, if you pluck it like a guitar string, it will vibrate at a certain frequency. Some OEMs will provide the frequency specification for the timing belt. You can measure the frequency with an app on a smartphone.
Excessive arm movement or bounce due to a worn damper: The damper moderates the action of the tensioner spring in much the same way that a shock absorber dampens a vehicle`s suspension. As the damper wears, the tensioner arm can bounce away from the belt, causing excessive belt slippage.
The timing belt idler torque specs vary between engines. In some engines, it`s 33 ft lbs of torque. In other engines, it`s 50 ft lbs. In others, it`s 17 ft lbs.
Ticking Sounds
The teeth of the timing belt make it sound different from the other belts in your engine, such as a serpentine belt. Generally, a timing belt that goes bad makes a noticeable ticking or clicking timing belt sound that is unusual.
If your car`s belt tensioner is wobbling, it is important that you take prompt action and replace the faulty part. Even if you are slightly concerned that your belt tensioner might be wobbling, it is best to take your car to the shop or replace the part yourself.
If the tensioner is loose the belts may squeak or squeal, especially when the engine is first started. It is also possible for the tensioner pulley or bearing to wear out, in which case the vehicle will produce a grinding noise from the pulley.
The allowable tensile strength varies from 190N to 1400N, depending on the belt width.
To prevent the timing belt from failing, the timing belt, tensioner and idler pulleys should be replaced every 50 to 70,000 miles.
To prevent the timing belt from failing, the timing belt, tensioner and idler pulleys should be replaced every 50 to 70,000 miles.
You should expect to replace your belt tensioner in the 40,000-70,000 mile range. It is also customary to swap more than one part simultaneously, usually a worn-out pulley from other systems and even the serpentine belt itself.
Most modern cars that roll off the dealer`s lot as a new vehicle will have a 60,000 to 100,000-mile life expectancy for the serpentine belt, tensioners, and idler pulleys.
Relevant Questions and Answers :
the most relevant questions and answers related to your specific issue
Replaced a timing belt and timing belt tensioner pulley. Still wont run. Why?
ANSWER : If you broke the timing belt while driving then you may have bent the valves. You should have the engine compression checked to see if you are loosing compression due to bent valves. If compression is low then have cylinders leak tested to see which cylinder is leaking and what valves are bent.
after replacing belt, idler pulley, and tensioner pulley tahoe still sqeaks in the morning?
ANSWER : At the next cold start, try this: Take a spray bottle with some water and spray the belt then start it. If you hear the noise, then the problem may not be with the belt or tensioner. If you do hear it, then it’s possible that one of the pulleys (a/c,water pump,etc) may be slightly glazed or out of round. It’s also possible that a bearing, such as in the water pump, alternator, or a/c compressor clutch may be the issue. Sometimes a bearing that is on it’s way to failure can squeal when cold until it warms up. Alternator bearings are a common source. A mechanics stethoscope may be a good tool to locate a squealing sound. Since the noise is primarily on a cold start, the vehicle may need to sit for several hours or even overnight to get the noise to occur and found with the stethoscope.
I have a 96 Ford ranger with cel p0340 I have recently done a timing belt, engine runs great replaced cmp sensor cel still on
ANSWER : Hi There,
This may happen for a couple of reasons. First, check to be sure that the connections to the sensor are clean and not faulty or broken. Secondly, check to be sure you replaced the correct sensor as there are two camshaft position sensors in some applications. If you need further help with this, please reach out to us here at YourMechanic as we are always here to help.
This may happen for a couple of reasons. First, check to be sure that the connections to the sensor are clean and not faulty or broken. Secondly, check to be sure you replaced the correct sensor as there are two camshaft position sensors in some applications. If you need further help with this, please reach out to us here at YourMechanic as we are always here to help.
hi- i got an estimate to replace my timing belt and water pump for my 2012 pilot. Do these figures seem right? Timing belt (35.00)
ANSWER : Hi there. That is a fairly good and detailed estimate for this type of service. It also falls within the price estimation to have a mechanic shop complete this service. However, you might want to consider a third option, of having a professional mobile mechanic come to your location and complete the timing belt replacement and water pump replacement. Simply click the blue links to receive an estimate for both services.
Timing belt is tight and yet appears to be slipping several teeth when belt is rotated,
ANSWER : This is okay since there are more notches on the belt than the amount on the sprockets. Once you aligned the first time the belt marks will almost never line up perfectly again. The marks are used to put the belt on correctly. They aren’t used as an indicator after the engine is turned again. You should be okay to start the motor as long as timing marks on pulleys line up. If you run into any issues, have a certified technician, like one from YourMechanic, assist you with the replacement of the timing belt.
Car wont start after replacing timing belt but I know timing is spot on. What could it be?
ANSWER : Hi there, thanks for writing in.
Well if the car ran before you did the timing belt, but now doesn’t run after, I am or course going to say that the likely scenario is that the timing is off. Make double and triple sure that you’re using the correct marks on the camshafts and crankshaft, and make sure that the belt is properly tensioned. If all this is correct, it’s not impossible that something else failed, just highly unlikely. The next step after verifying the timing is correct would be to check fuel pressure and run a compression check. You would normally want to check for spark, but you have already done that. If the timing belt was off before and you turned it over at all, it could have damaged valves and that would cause the motor to have no compression. If these checks don’t yield any results, then you should consider contacting a professional technician, such as one available from YourMechanic, to diagnose the no start condition.
Just replaced both belts on 2008 Fx35 infiniti.
ANSWER : Hey Dan, thanks for inquiring. I don’t know that you necessarily need to replace your pulleys, neither tensioner or idler. However, if you are hearing a squeaking from your engine and suspect the pulleys are the problem then replace them as needed. I don’t think you really need to replace pulleys every time you replace the belts.
Serpentine belt is rubbing on the engine cover at the belt tensioner pulley 2004 Hyundai Tiburon
ANSWER : Hi there – I would start by doing a visual inspection of the serpentine belt, and the pulleys – are they visually in line? If not, which pulley is out of line in the direction of the engine cover? Are there bushings on the alternator mount which have softened, and are allowing the alternator to "give" such that the serpentine belt is close to the cover? The crankshaft pulley is not likely moving at all. Is the cover where the rubbing occurs coming loose, and moving into the serpentine belt? For assistance, I would recommend a serpentine belt replacement by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, give you an accurate assessment of damage and cost estimate for repairs.
