I have a SOHC
I replaced all the timing chain components (chain, tensioner, gears, guides,etc). The job went pretty well except for the fact that i bent the metal gaskets for the block to front cover oil passages and had to replace them. Other than that I was pretty proud of the job and followed the directions from this forum ( I love you Guys). Like I said it went well for about a month. The rattle is back and it is worse. Now instead of rattling at idle, it rattles all the time. It only stops after 3000rpm. I have taken off the valve cover and inspected the components, especially the tensioner. It is not applying the pressure needed to tighten the chain. I know it is oil fed, is this feed the only reason it is not applying enough pressure. My oil light comes on at start-up then quickly goes off. Is this because oil is leaking past the tensioner bolt? I am assuming that at 3000rpm the presasure is enough to apply enough pressure to push the bolt onto the guide. When I had the valve cover off I used a screwdriver to push the guide tight and pull the slack out of the chain and the tensioner followed. But cannot hold it tight after startup. Could I have gotten a bad tensioner? I guess it is possible, but what an effort for nothing. Like I said it worked for about a month before it came back. What can I do???
thanks for reading all that crap, Pat.
Timing Chain Question For anyone who has changed it.
The chain tensioner on the SOHC is not oil fed, it is spring loaded. The only reason i can think is your spring on the tensioner is bad.
And if your oil light is coming, the sound you are hearing is more likely piston slap due to lack of oil or rocker arm knock, also due to lack of oil pressure. First, make sure you have enough oil (duh, i know). Then i would have to think about changing the oil pump.
And if your oil light is coming, the sound you are hearing is more likely piston slap due to lack of oil or rocker arm knock, also due to lack of oil pressure. First, make sure you have enough oil (duh, i know). Then i would have to think about changing the oil pump.
tHANKS FOR THE RESPONSE jnm240. i APPRECIATE THE TIME. tHE OIL LIGHT IS ONLY MOMENTARY. iT ONLY OCCURS ON THE FIRST START OF THE DAY AND lasts for about a second. That really irritates me. Changing the chain was a lot of work. It took me 2 days. All of that for a month of needed silence, then again. If it is just the spring then I can take care of that. What a pain though.
I have another question. Does the SOHC have a AAI. On the FAQ list they seem to only mention the DOHC. I cannot locate mine. I am having an idle problem at Normal Operating Temp and a hesitation at cruising speeds. I do not know what it is. I cleaned out the MAF and the throttle body. I believe all vacuum lines are connected. I am just unsure.. Any ideas.
I have another question. Does the SOHC have a AAI. On the FAQ list they seem to only mention the DOHC. I cannot locate mine. I am having an idle problem at Normal Operating Temp and a hesitation at cruising speeds. I do not know what it is. I cleaned out the MAF and the throttle body. I believe all vacuum lines are connected. I am just unsure.. Any ideas.
If your car is stock, you should not need to adjust the idle. All 240SX's are know for their coolant temp sensor connection corroding and sending a faulty reading to the ECU, which creates an overly rich condition, which would cause hesitating and backfiring and smoke from the tailpipe. Check this first, i would bet it has some corrosion on it. Also, wiggle the wire coming off the MAF sensor, you might have shorted it when you cleaned it.
But the thing is, if your chain isnt properly tensioned, then the camshaft is going in and out of time with the crank, which would cause irradic idle and hesitation until there is enough tension to keep the two in time with each other. I would look harder into the tensioner problem before i started messing with the idle at all.
Let us know what happens.
But the thing is, if your chain isnt properly tensioned, then the camshaft is going in and out of time with the crank, which would cause irradic idle and hesitation until there is enough tension to keep the two in time with each other. I would look harder into the tensioner problem before i started messing with the idle at all.
Let us know what happens.
I am working on the chain tension right now. The chain has slack on the side opposite the tensioner. The tensioner side is tight and the opposite is loose enough to rattle. If i put a screwdriver behind the tensioner guide and put some pressure on it the slack pulls out of the other side. But when i put the slack back in the opposite side, the spring doesnt have enough ooomph to pull it back out. How is it possible that the original spring could be strong enough for 10 years and the new spring only lasts 2 months? Is there nothing that assists the spring?The piston aft the spring moves in and out smoothly. The tensioner has alot off push in it. Not enough where I cant push back in, but it has alot of tension.
I guess Ill have to replace the spring, but if this is an every month thing , crap. The negative side of my brain tells me that I will not remove that go*amn front cover again. The good thing is is that I can replace the spring without doing so. If i put a rag down in there and remove the cam gear. I should be able to replace the spring just by slowly moving the tensioner guide until I can pull the spring out. Then replace rinse and repeat. This sucks.
I guess Ill have to replace the spring, but if this is an every month thing , crap. The negative side of my brain tells me that I will not remove that go*amn front cover again. The good thing is is that I can replace the spring without doing so. If i put a rag down in there and remove the cam gear. I should be able to replace the spring just by slowly moving the tensioner guide until I can pull the spring out. Then replace rinse and repeat. This sucks.
The idle problem is when it is at Normal Operating temp. It drifts up and down and occasionally stalls. From 300 rpm to 1400 rpm. Exactly as described when the IAA is mentioned. The surging is only at cruising speed when the throttle is 10 - 30 percent open. It hesitates as if and orange was stuck in the exhaust. Until; I give it a little extra gas then the orange shoots out. It happens all the time and not until just recently.
Well the slack side should have a little slack in it, but not enough to rattle by any means. I really hate it for you, because i cant believe the tensioner went bad so quickly either.
As for the coolant temp sensor, you are correct. There are actually 2 plugs/sensors right by the burp valve on the intake manifold. The smaller one is for the gauge, the larger 2 wire one is for the ECU.
The IAA (Idle Air Adjusting) unit is located on the back side of the upper intake plenum (see where it says ECCS, its right behind the S on the end).
Some things to check are:
the throttle body (make sure its clean)the fuel pressure regulator (apply vacuum pressure to pressure regulator after disconnecting vacuum hose, and check idle)start and run engine with engine temperature sensor connector disconnected (check idle)check ECU for codes
let me know if any of this helps at all.....
As for the coolant temp sensor, you are correct. There are actually 2 plugs/sensors right by the burp valve on the intake manifold. The smaller one is for the gauge, the larger 2 wire one is for the ECU.
The IAA (Idle Air Adjusting) unit is located on the back side of the upper intake plenum (see where it says ECCS, its right behind the S on the end).
Some things to check are:
the throttle body (make sure its clean)the fuel pressure regulator (apply vacuum pressure to pressure regulator after disconnecting vacuum hose, and check idle)start and run engine with engine temperature sensor connector disconnected (check idle)check ECU for codes
let me know if any of this helps at all.....
Just to let you know I found the problem and I appreciate your time. I tried what you said and it didnt help. So I cleaned out the EGR, BPT valve and relative hosing. Still the same problem. So I pulled the codes form the ecu (which I never thought to do) and it gave me code 33. Which was the o2 sensor. Changing that fixed it all. Atleast today. Thanks again.