7A-FE lack of power, After putting cams in right position car has less power in low RPMs Options

[Grega]

Hi, I changed water pump and timing belts yesterday, and when I removed the head gasket I saw that the timing mark on exhaus cam was not lined up with the arrow that marks where dot must be


^ Here is the image, taken from Smaays topic about building the 7A-FE , I hope that's not wrong. That is how the engine must be lined up with all marks on timing belt. But when I lined up the engine with other timing marks, the arrow and the mark on gear weren't lined up, but the dot on cam was leaned one gear to the left. I don't know if I am speaking in correct language

So I'm giving you a picture of how it was (not the actual one)


After pulling my cam out and inserting it in in the right position, I ended up with putting my timing belts on and everything together and the I ran the engine. I took nearly 5 seconds from turning the key to starting the engine which seems very wierd to me, because my car normally starts right after i turned the key and has an iddling RPMs when it was cold around 1800 and around 1150 when warm. I rotated a rotor cap for about 2° and now car idles at about 850RPMs which is normal and the (I don't know the right word for this, but direct translation is pre-ignition - you know, thoose marks on the plastic cap on timing belt that are from 0 to 20) raised from 0-5 on 10-15 and car gained some power, but it's still not strong as it was before changing the cam gear for one gear. I hope you guys undertand what am I asking about, before doing anything of this my car runs very strong in low RPMs and still strong in high RPMs which is normal. After changing the exhaust cam gear car barelly start cold, has high RPMs , "pre-ignition" was between 0 and 5 and car had literally no power till it reached 3k RPM, after 4k RPM you could feel the BUM when engine got the power. After rotating the rotor cap car got normal idling RPMs, it gained a little power at lower RPMs but still not strong as it was and the "pre-ignition" changed to 10-15. What else to check, or just put the engine back on how it was and if it's possible that engine had more power before with changed cam gear for one gear? Thank you guys!!

[Grega]

anyone??

[mandrek]

the marks on the timeing belt cover that you are refering to as "pre-ignition" is actualy your ignition timeing.. but unless you rotated the dizzy wile the car was in diegnotics mode ( a pair of pins that you have to jump in the "diegnostics box", you will not have adjusted the timeing to the car properly. as far as that goes i would put it back to the way it was before.

as for the rest. what it looks like is posible that you "jumped a tooth" or moved one tooth over (left or right) from your over all timeing,, as in the corilation between the gear on the crank an the camgear.. i have not gotten to this step on my 7A yet, but the samething was happening to my buddy's b18 when we went to fire it up for the first time after a turbo install. and all it was, was just off by one tooth. it did the exact same thing too.. hard to start, once it did sounded like crap, ideled wrong, then die.

best thing IMO, is to just put it back the way it was , and then try to diegnose the issues one step at a time.

also. use this info.

[RabidTRD]

Why did you take the cam out and adjust it that way? Just curious as to why you didn't just rotate the cams before putting the belt on. If there is no tooth damage, the likelyhood of it "hopping a tooth" is very low without damage. Are there marks on both intake and exhaust cams and one was on but the other off?

[Grega]

Why did you take the cam out and adjust it that way? Just curious as to why you didn't just rotate the cams before putting the belt on. If there is no tooth damage, the likelyhood of it "hopping a tooth" is very low without damage. Are there marks on both intake and exhaust cams and one was on but the other off?

I did it that way because all other marks were as they should be, only this mark on exhaust cam was off for one tooth, so that seems like the only way to set this proprely. Today car starts as soon as I turned the key but it has no power then I shut the car and try to start it back and it barely started in 3d attempt. For now the only way to fix this to set thome cam as it was, although this is for one toot off

[Bitter]

it probably wasn't a tooth off, the cams are slaved together, so if one is in time then both are, otherwise it would have ran like crap from the factory. You'll need to set the cam back where it was and use the timing marks on the belt sprocket.



yes, those dots are to align the two cams to each other, the two dots need to point at each other...but don't get them confused with the installation marks which are different. Basically, your exhaust cam is out of time and who knows where the intake is now in relation to top dead center. You need to take it all apart and re-time it correctly then reset the ignition timing to 0 and then set the timing correctly as well.

This post has been edited by Bitter: Dec 24, 2011 - 11:26 AM

[Hafkai]

..was not lined up with the arrow that marks where dot must be..

The arrow on the bearing cap has nothing to do with the dot on the camshaft ..the dots are there to allign the cams with each other.
Like the others already said the cam was probably in correct position. Have you secured the cam gear of the intake camshaft with a screw while taking it out? If not you have to preload it or your timing will never be correct.
If you don't have a manual for this engine i could send you one.

[Smaay]

the dots on the slave gears are supposed to line up, the dot on the timing belt gear lines up with the mark on the timing cover