How can i do timings when forgotten to put markings on disassembling??

The procedures vary depending on design. Fortunately most engine manufacturers usually make timing marks if you know where to look and for that information you need a repair manual.

Some engines do not have timing marks but correct timing can be achieved by following the correct procedure and for that, again, you need a repair manual.

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ALL Timing marks should be lined up correctly. If they are out of position you could do some VERY expensive damage to the engine.

there are timing marke on the cam pulleys and crank shaft this is assuming that cams havnt been loosend

its a good idea to set the engine at TDC before disassembly. note the location of timing marks on crank and cams to familiarize your self when you go to re-install.

There is a Toyota Technical Service Bulletin issued for this:-
T-SB-0291-08 September 11, 2008 2GR-FE Valve Timing

Procedure Service Category Engine/Hybrid System Section Engine Mechanical Market USA Applicability YEAR(S) MODEL(S) ADDITIONAL INFORMATION 2005 - 2009 Avalon 2007 - 2009 Camry VDS(s): BK46K 2008 - 2009 Highlander 2006 - 2009 RAV4 Engine(s): 2GR VDS(s): BK31V, BK32V, BK33V, BK34V, ZK31V, ZK32V, ZK33V, ZK34V, ZK35V 2007 - 2009 Sienna Introduction This service bulletin provides information regarding valve timing inspection and service guidelines for vehicles equipped with 2GR-FE engines. © 2008 Toyota Motor Sales, USA Page 1 of 5 T-SB-0291-08 September 11, 2008 Page 2 of 5 2GR-FE Valve Timing Procedure Introduction (Continued) Figure 1. 3 2 1 5 9 8 7 6 4 1 RH Bank Intake Camshaft Timing Gear 2 RH Bank Exhaust Camshaft Timing Gear 3 RH Bank No. 2 Timing Chain 4 Crankshaft 5 Idler Gear 6 Timing Chain 7 LH Bank No. 2 Timing Chain 8 LH Bank Exhaust Camshaft Timing Gear 9 LH Bank Intake Camshaft Timing Gear Warranty Information OP CODE DESCRIPTION TIME OFP T1 T2 N/A Not Applicable to Warranty © 2008 Toyota Motor Sales, USA T-SB-0291-08 September 11, 2008 Page 3 of 5 2GR-FE Valve Timing Procedure Inspection 1. Set the No. 1 cylinder to TDC/compression. A. Set the timing mark to 0 on the timing chain cover by rotating the crankshaft clockwise. B. Verify the timing marks on the camshaft timing gears are in general alignment with the timing marks of the camshaft bearing cap: TIMING MARK IDENTIFICATION CYLINDER BANK INTAKE GEAR MARK EXHAUST GEAR MARK RH Bank (Bank 1) Small Mark Single Line LH Bank (Bank 2) Large Mark Double Line HINT When the engine is correctly timed, the timing marks will NOT perfectly align. Figure 2. Figure 3. RH Bank Exhaust Camshaft Timing Gear 1 2 1 Bearing Cap Timing Mark 2 Gear Timing Mark Figure 4. RH Bank Intake Camshaft Timing Gear 2 1 1 Bearing Cap Timing Mark 2 Gear Timing Mark © 2008 Toyota Motor Sales, USA T-SB-0291-08 September 11, 2008 Page 4 of 5 2GR-FE Valve Timing Procedure Inspection (Continued) Figure 5. LH Bank Intake Camshaft Timing Gear 1 2 1 Bearing Cap Timing Mark 2 Gear Timing Mark Figure 6. LH Bank Exhaust Camshaft Timing Gear 1 2 1 Bearing Cap Timing Mark 2 Gear Timing Mark HINT If the timing marks appear vastly out of alignment, turn the crankshaft one revolution (360 ) clockwise and note the position of the timing marks. Component Removal Guidelines 1. If engine disassembly is required that involves removing the camshafts or timing gears, set the #1 cylinder to TDC compression, wipe away any oil, and mark the following items in relation to each other prior to disassembly: • Timing gears • Timing chain • Timing chain No. 2 NOTE This relationship MUST be maintained. The intake gear is timed in relation to the crankshaft via the timing chain; the exhaust gear is timed in relation to the intake gear via the No. 2 timing chain. © 2008 Toyota Motor Sales, USA T-SB-0291-08 September 11, 2008 Page 5 of 5 2GR-FE Valve Timing Procedure Component Removal Guidelines (Continued) 2. If NEW camshaft timing gears or the No. 2 timing chain are being installed, the two yellow links on the No. 2 timing chain can be used to ensure correct relationship between the intake timing gear and the exhaust timing gear. Figure 7. 1 1 Yellow Link A. Align the paint mark on the timing chain with the intake gear timing mark (to ensure the intake gear is correctly timed to the crankshaft). Figure 8. RH Bank and LH Bank 3 3 4 3 3 4 5 4 5 4 1 2 1 RH Bank 2 LH Bank 3 Yellow Link 4 Gear Timing Mark 5 Timing Chain Paint Mark B. Align the two yellow links on the No. 2 timing chain to the timing marks on

adjust your distributor

I think you should check your timing again, check the firing order of the distributor and if they are with there corresponding spark plug. Did you mark the connector or label them before disassembling. Maybe u left the timing in exhaust instead of compression

timing chain marks. 1.6 nissan

when starting push gas, if runs
idle valve (IAC) stuck,replace or disassemble and clean the burrs
has two time this promblem