Did my timing belt slip or did I mess up the install?
An engine that idles fine briefly before running rough, dying, or refusing to rev past 2,000 rpm points directly to valve timing misalignment from the recent replacement rather than a slipped belt. This prevents the car from running reliably despite new components, as incorrect timing creates unburned fuel issues, strong petrol smells, and misfires.
What the numbers show
Counted from the threads quoted below. How we count
- Most of it landed at once — the busiest month was September 2026, with 10 people.
- It is not one crowd: 11 people on Reddit and 1 on Stack Exchange ran into the same thing.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
Found another way around this?
Share your steps and trade-offs so fellow engineers don't have to reinvent the wheel. No account required.
- 1removing the valve covers and timing cover to investigate2 people mentionedDid this help you?
- 2Taking everything apart to inspect and reassemble the componentsDid this help you?
- 3Disconnecting the battery to reset the ECM to test for open-loop maskingDid this help you?
- 4Replacing multiple fuel system components such as the high-pressure fuel pump, fuel rail, pressure sensor, injectors, low-pressure pump, and ignition coilsDid this help you?
- 5Checking timing twice with locking toolsDid this help you?
- 6Monitoring PIDs and sensor voltages using FORScanDid this help you?
- 7Tracing wiring looms for potential chafing or shortsDid this help you?
- 8manually rotating the crankshaftDid this help you?
- 9jumping the starter relay to crank the engineDid this help you?
- 10Checking timing alignment manually by rotating the crankshaftDid this help you?
- 11Jumping the starter relay to crank the engine and isolate the soundDid this help you?
- 12Performing a cylinder leakage test and setting the timingDid this help you?
- 13Disassembling the engine for head repairDid this help you?
- 14turning the crankshaft by hand twice to check alignment and belt tensionDid this help you?
- 15Stripping everything back to inspect components and timingDid this help you?
- 16Checking cylinder compressionDid this help you?
- 17Verifying oil levels in the sumpDid this help you?
- 18Replacing various ignition and fuel system components personallyDid this help you?
- 19Consulting online forums like Reddit for troubleshooting directionDid this help you?
- 20marking positions with a paint pen prior to serviceDid this help you?
- 21cranking the motor by hand multiple times to check for smooth movementDid this help you?
- 22Replacing parts through trial and error such as the VVT solenoid, valve cover, camshaft position sensor, or timing chain tensionerDid this help you?
- 23Swapping intake and exhaust solenoids to test for faulty replacement partsDid this help you?
- 24Inspecting internal engine components and screens for debris or oil clogsDid this help you?
- 25Posting on mechanic forums for guidance before attempting to start the engineDid this help you?
- 26Replacing valve sealsDid this help you?
In their words
Unedited, grouped by where they were said, most upvoted first within each place, each linked to the thread it came from.
“So i’d just like a second opinion on whether i’m fine. I’m crazy paranoid that it jumped a tooth randomly or i bent a valve in the process lol.”source ↗
“I'm like 87% sure my 07 camry jumped timing, it's got a 2az-fe 2.4 l engine with 205897 miles. Compression reads 90 120 120 120 and 2 of the bolts for the ignition coils are stripped from the cover.”source ↗
“I’m trying to diagnose this metallic thumping/rattling engine noise on a 2014 Kia Sorento V6 3.3L and would really appreciate some advice from anyone more knowledgeable and mechanically experienced than I am.”source ↗
“Then, while driving on the highway, I suddenly felt what seemed like something gave away, immediately followed by a metallic rattling noise from the engine.”source ↗
“I found silver/aluminum-looking metallic flakes/shavings in the engine oil pan, which obviously concerns me.”source ↗
“Mechanic recently replaced the engine, and beforehand, I personally...”source ↗
“The mechanic has replaced the engine, but is telling me he is stuck and doesn't know what the issue is.”source ↗
“I just really need some advice on a direction to point him in.”source ↗
“Since the swap it starts and runs, but: - Idles nicely for a few seconds, then gradually runs rough and dies. - Sometimes won’t rev past ~2,000 rpm. - Occasionally hits what feels like a hard limiter with a pop. - Strong petrol smell and a little white smoke.”source ↗
“At this point I’m wondering if I’m chasing a wiring, PCM, or control issue rather than another failed fuel component.”source ↗
“I’ve already swapped the HPFP, rail, FRPS, injectors, seals, LP pump and coils, so I’m running out of components to blame”source ↗
“i replaced the timing kit, but after i started havin cold start misfires and hunting idle and it sounds like this until i start driving, recently i started having the cold start rattles too, i have no error codes.”source ↗
“Little nervous pulling the head, the 2az is notorious for bolts stripping from the block.”source ↗
“But now it’s like very difficult to spin the engine and the timing chain seems to be very tight. Not sure if that’s how it should be normally or if I have done something wrong.”source ↗
“New timing belt and water pump, all seals on side of belt, oil change(5w-30) and car started smoking like this. It smokes on cold starts after and when in neutral.”source ↗
“I tought it might be the valve seals, replaced them however smoke still prevails.”source ↗
“So it's a mystery. Did the timing belt somehow slip ? New tensioner, and I did the bleed procedure as instructed and remembered to remove the "grenade" pin. If it did slip, what did I do wrong, and why hasn't it happened again ?”source ↗
“I’m trying to diagnose this metallic thumping/rattling engine noise on a 2014 Kia Sorento V6 3.3L and would really appreciate some advice from anyone more knowledgeable and mechanically experienced than I am.”source ↗
“Then, while driving on the highway, I suddenly felt what seemed like something gave away, immediately followed by a metallic rattling noise from the engine.”source ↗
“I found silver/aluminum-looking metallic flakes/shavings in the engine oil pan, which obviously concerns me.”source ↗
“I suppose I won't know for sure if it's all correct until starting the engine back up, but does this all sound correct?”source ↗
“I have had a persistent problem with a P0014 code (exhaust camshaft over advanced) for about a month now. I recently replaced the VVT solenoid, and don’t have any codes again (yet) but the symptoms are still present. Fluctuating RPMS at idle, rough idle, and won’t start on first crank.”source ↗
“I feel like I’m running out of ideas here. Should I try to replace the camshaft position sensor, or the timing chain tensioner? Taking off the timing cover and inspecting the chain is the last thing i’d prefer to do, but like I said, I’m afraid I’m running out of options here, please help!”source ↗
Where this came up
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