How to replace timing chain

if you adjusted timing [which shouldnt have to be done unless distributor was disturbed]] check timing chain for skipped tooth or stretch

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

timing chain check....place cylinder 1 at end of compression then the timing mark place at 0 distributor rotor should be to number 1 cylinder. if not timing chain could be out of teeth
3 major things for engine is air,fire,fuel.then you say you change the distributor ....is it in good position???

There are two kinds of timing, cam timing, and ignition timing. You don't adjust cam timing, it is set when the timing chain is installed. The timing chain cover is supposed to have a pointer welded to it with marks that line up with a mark on the harmonic balancer. (depending on the year of you engine these marks veri in appearance. Ignition timing is set while the engine is running with a strobe light that is triggered by the number one spark plug. On this engine (if it's stock) around 8-10 degrees BTDC. The ignition timing advances with cetrifical weights inside the distributor as well as a vacuum diaphragm. If either of these fail you will have a performance issue with a lack of power, and acceleration. If you are concerned about the cam gear being worn out yes they do wear out. Chevy made the gear teeth on the cam gear out of nylon to make then quieter, the replacement gears are usually cast iron. If you are thinking about changing the timing gears, the crank gear has to be pulled off with a puller, a lot of guys don't bother since it doesn't wear like the cam gear.

I would check to make sure its the timing chain they normaly don't go first on that engine. The crank shaft pisition sensor or the disturbtor shaft can look like the timing is the problem.But if you have broken a tooth on the gear or something you need to remove the radaitor the water pump the timing cover you can unbolt the upper gear the lower one you have to pull. Set the engine up so # 4 cylinder is at the top of the compression stork. install the gears so the mark is down on the upper gear and up on the lower gear and they line up in the middle # 4 is the front right hand side when faceing the engine from the front and the vehicle be on correctly timed.

whether it's a four or six cylinder, it's still a chain

Timing Chain and Gears REMOVAL & INSTALLATION 1.9L Engine NOTE: The following procedure requires the use of the puller tool No. J-25031 or equivalent, and timing sprocket installation tool No. J-26587 or equivalent.

1. Remove the timing (front) cover from the engine.
2. Lock the shoe on the automatic adjuster in fully retracted position by depressing the adjuster lock lever. NOTE: To remove the timing chain, it may be necessary to remove the camshaft sprocket. Before removing the timing chain, be sure to align the timing marks.
   
3. Remove timing chain from crankshaft sprocket.
4. Check the timing sprockets for wear or damage. If crankshaft sprocket must be replaced, remove the sprocket and the pinion gear from crankshaft using the puller tool No. J-25031 or equivalent.
5. Check timing chain for wear or damage; replace as necessary. Measure distance "L'' (40 links) with the chain stretched with a pull of approximately 22 lbs. (98N). Standard "L'' value is 15 in. (381mm); replace chain if "L'' is greater than 15.16 in. (385mm).
6. Remove the automatic chain adjuster-to-engine bolt and the adjuster.
7. To check the operation of the automatic chain adjuster, push the shoe inwards, if it becomes locked, the adjuster is working properly. The adjuster assembly must be replaced if rack teeth are found to be worn excessively.
8. To remove the chain tensioner, remove the "E'' clip and the tensioner. Check the tensioner for wear or damage; if necessary, replace it. Fig. 1: Timing chain guide and tensioner - 1.9L engine
   
   
9. Inspect the tensioner pin for wear or damage. If replacement is necessary, remove the pin from the cylinder block using a pair of locking pliers. Lubricate the NEW pin tensioner with clean engine oil. Start the pin into block, then place the tensioner over the appropriate pin. Position the E-clip onto the pin, then (using a hammer) tap it into the block until clip just clears tensioner. Check the tensioner and adjuster for freedom of rotation on the pins.
10. Inspect the guide for wear or damage and plugged lower oil jet. If replacement or cleaning is necessary, remove the guide bolts, the guide and the oil jet. Install a new guide and upper attaching bolt. Install the lower oil jet and bolt, so that the oil port is pointed toward crankshaft. To install: Fig. 2: Timing chain alignment and installation - 1.9L engine
    Fig. 3: Inspecting the timing chain for wear
    
    
11. Install the timing sprocket and the pinion gear (groove-side toward the front cover). Align the key groove with crankshaft key, then drive it into position using installation tool No. J-26587 or equivalent.
12. Turn the crankshaft so that key is turned toward the cylinder head-side (No. 1 and No. 4 pistons at TDC).
13. Install the timing chain, align the timing chain mark plate with the mark on the crankshaft timing sprocket. The side of the chain with the mark plate is on the front-side and the side of chain with the most links between mark plates is on the chain guide-side. Keep the timing chain engaged with the camshaft timing sprocket until the camshaft timing sprocket is installed on the camshaft.
14. Install the camshaft timing sprocket so that it's marked-side faces forward and it's triangular mark aligns with the chain mark plate.
15. Install the automatic chain adjuster.
16. Release the lock by depressing the shoe on adjuster by hand, and check to make certain the chain is properly tensioned when the lock is released.
17. Install the timing cover assembly.

fuel pressure regulator it is located on the spider pump behind the throttle body

Your vehicle has a timing chain, not a belt. There is no regular maintenance interval on the chain. If it starts to clatter at idle, it may be time to replace, otherwise, do not be concerned