Severe pinging after timing chain replacement

**Shifty** · 26-04-2006, 08:43 PM

Hi guys

Replaced the timing chain on my 22RE, because it was rattling (as they do).

It's all back together now, but it's pinging like a bastard. Runs fine, starts fine and drives fine.. as long as you don't go past 15% throttle - at which point war veterans run screaming from the rat-tat-tat! It even pings on free rev if you give it 50% throttle.

There are only three things I can think are:

1. Ign/Dizzy timing: I have checked with a timing light and it's spot on.
2. Cam Timing: it looks to be lined up correctly, although if I was to be a perfectionist it's off by about 4mm. If I moved it one tooth (a furgin big job, mind you) it'd be off by exactly the same distance in the other direction.
3. Some kind of vacuum leak or transposed hoses to the distributor vacuum advance. I've swapped the latter with no improvement and the former I haven't been able to find any signs of.
4. Leak between the TB and AFM. The hose is a little dodgy but it always was, and has been on other 22RE's I've had so I can't see this being a huge problem - especially as it wasn't before and I can't see any new damage to it.
Can anyone offer help? I don't want to pull the thing apart all over again, ESPECIALLY if that doesn't solve it.

**30psi 4agte** · 26-04-2006, 09:16 PM

Looks like it may be a tooth out.

what is the dizzy position like in regards to the adjustment slot. Does it sit in the middle of its adjustment?

Did you disconnect vac advance when you set timing?

**Earlyrolla** · 26-04-2006, 10:02 PM

If you have done all these things and the dizzy timing is definitely right then... Are you sure the noise you are hearing is the engine pinging?

**limbo** · 27-04-2006, 01:36 PM

did you aline the cam properly to TDC when you put back the chain? Not sure if the chain has any markings like the belts do though. Also is the chain the exact length of you old one?

I don't think your gonna be able to diagnose without taking it apart again.......

**Shifty** · 27-04-2006, 02:06 PM

I aligned everything before it was reassembled - I did some testing last night.

I set the crank to #1 TDC and puleld the cam cover off. The mark on the cam pulley is a few mm counterclockwise to TDC, but if I advanced it one tooth it would be off by the same distance clockwise from TDC.

The only thing I can think is to pull it apart and advance it that one tooth in the hope that is the problem. I'll be crabby if that's not it!

Thinking about it, having the cam a few degrees counterclockwise would make the cam timing late which means that the exhaust valves are not opening until well after the spark has fired - as it fires a few degrees BTDC, that extra few degrees would accentuate this.

**ra40celica** · 27-04-2006, 05:15 PM

id be looking at your harmonic balancer, the rubber inside of these can break, it could have possibly shifted a bit, there for you arent getting ignition timing right. i dont see that the cam alignment would cause pinging, i would think it would be more likely to backfire.

Just back the timing off till it stops pinging, if it drives okay them it should be alright,

**Shifty** · 27-04-2006, 07:05 PM

Yep, I've already checked the crank pulley out and there's definitely no issue there - the piston reaches TDC at the same point as the crank marker reaches TDC.

I, too, would have thought that the cam pulley being off a tooth would introduce backfiring rather than pinging... but I've backed the dizzy off all the way, including even backing it off a whole tooth...

**30psi 4agte** · 27-04-2006, 08:19 PM

If the cam timing is advanced too far it will deff ping ! Its the same as your ignition timing

**slide86** · 27-04-2006, 08:27 PM

the marks are there for a reason. you should really have them lined right up.

I had the same problem when i did the head on the mighty CA20. i coudnt get the cam to line up properly, i had to get a mate to hold the cam in the right spot and then i put the belt on.

the reason why it wouldnt sit on the mark is cause the cam was in an overlap state and the valve springs were forcing the cam to turn and not line up.

Perhaps you could try the same thing. get somone to hold the cam in place and then fit the chain up. then refit the dizzy in the correct place and check your timing, hopefully its gone to the correct position!

**Shifty** · 27-04-2006, 08:40 PM

the marks are there for a reason. you should really have them lined right up.

Thanks for the undertones there. Anyway, I did line it up, triple checked and had two other people re-check for me... it was lined up as best as possible but there were two teeth that looked close-ish, I chose the one that looked the most right.

As the motor rotates clockwise the passenger's side of the chain had to be taut when it was installed... doing so meant that the cam mark could not be absolutely 100% spot on the top but it was within a poofteenth. I could have put it on the next tooth with no problems (cam turns fine), but it looked less right than this one...

Apparently I chose wrong!

**Bananaman** · 27-04-2006, 10:02 PM

I've dealt with the exact same problem when i was doing a head gasket on a suzuki sierra 1L (long story). It seemed as though the cam was half a timing belt tooth off - it was literally impossible for me to get it 100% right. Checked and redid it half a trillion times and it just wasn't possible, i understand exactly where you're coming from.

The exception for me however, was that after putting it back together, it ran just fine

**Shifty** · 28-04-2006, 08:24 AM

Glad someone agrees. I've been playing with cars for years and this kinda wierd thing comes up every now and again.

I'll pull her apart tomorrow and jump her forward a tooth.