KRMaxima21

About a month ago my brother put some 89 octane into my car. This would be somewhat okay....if I didn't have a JWT ECU upgrade. Anyway, the car suddenly started to hesistate and miss under acceleration. I put some 93 octane and some SeaFoam into the tank and it went away but not before this ticking noise started coming from the engine. Some days it's loud as hell and you can hear it when idling and under acceleration. Then sometimes it just goes away and you don't hear it anymore and all of a sudden it comes right back. Could it be the timing belt? My friend thinks it's either a sticky lifter or an exhaust leak but I doubt it's an exhaust leak. Could it be I burnt out the o2 sensor or maybe the knock sensor? I'm guessing it's the knock sensor because it's making a LOUD knocking sound and the knock sensor has never been changed on this car in the 3 years I've had it. Any help would be much appreciated. If I didn't explain enough I apologize

ChrisCheezer

hey, replacing the knock sensor isnt a "tune-up" thing. very low chance its that, but it could be...
be a bit more discriptive and maybe we can help.
-do you still have a miss and or hesitation? after u dumped seafoam in the tank?
-does the noise effect the cars driveability?
-when the car was missing and hesitating it could of contaminated the O2 sensor.
-im thinkin its a belt issue (not timing) if its really loud and u can hear it...maybe a pully
-with that discription it could be a thousand things...

Phatsta

I have the exact same problem. I've had some trouble with my tranny recently, in fact it's in the repair shop right now, so it makes it a bit tricky testing.

Anyway, a while ago I left the car standing, not using it for a week. Due to the temperature variations in this darn cold country condensation in the fuel tank is a general problem for all who lives here. We think nothing of it coz all you need to do is pour some alcohol (not just any of course ) into the tank and the water is taken out. But this one time I didn't have any in my tank.

When I drove off to work that morning it suddenly died on me. Several times. It was hesitating and stopping all the time, so I had to restart the engine over and over again. I bought some anti-condense alcohol then the problem went away and I thought nothing more of it. Until this morning though... this loud ticking appeared. It's the sounds like the VTC tick (which I have as well), only it comes a minute after I start the engine. First I start, the VTC is ticking then goes away, then after a while it starts again, then goes away. Haven't heard it while driving yet, but somehow I suspect I will...

Would really like to know why the VTC (if that's what it is) starts ticking more often after the hesitation and dying happened...

KRMaxima21

Well the missing had went away and Iwas just getting the ticking sound but I've noticed my gas mileage has went down dramatically since. Yesterday it actually started the hesistation thing like the o2 sensor was going bad. I think I'm going to change it today but what I'm trying to figure out is where that loud noise is coming from. I wish I knew. I remember someone saying the knock sensor is like a microphone for the engine. I think I'm going to have the belts checked out today. Maybe one is not tightened enough or something. I honestly don't know. The noise is heard as soon as I start the car up. You can hear it in park and when I shift it into drive the noise then lightens up a slight bit but as I accelerate the noise gets louder and you can hear it very clearly and when it goes into second it slightly fades out a lil but can still be heard. The same as it goes into 3rd. The car doesn't miss at all when it's idling. When my o2 sensor was bad it did. I doubt it's the timing belt because if it was then if it missed from the timing belt the engine would be destroyed because the VG is an interference engine. Any VG owners ever have a similar problem? Also where is the knock sensor on this engine and would I be able to change it myself with the car on rhino ramps or on jacks?

tripleGmax

iTrader: (8)

are you sure its a ticking and not like a shuffling of cards sound? when i had an exhaust leak, i heard a ticking. if you can get undr the car or look in there to see if any of your exhaust manifold studs are broken, some of them are harder than heck to see. i know i could barely see mine at first but after running my car for awhile with the broken studs ( i had 4 in total) i could start to hear the sound get worse, i think i started to break more studs as i slowly saved up money to pay to have it fixed. anyway i guess with your mods, you might know what an exhaust leak is, but thats my 2 cents on what i think it is. if you have a sound clip of it, upload it somewhere, if u dont have space to upload, i can upload it for you on one of my servers.

Gregg

Wiking

- timing belt noise typically is constant, rev dependent, driving or stationary.
- sticky lifter possibly yes [=varying noise], not too bad... Nissan oil filter? When was last oil change?
- exhaust leak stays always 'same' under same conditions
- Knock sensor is a sensor. They just detect, but do not procduce... If the knock is related to ping, ECU delays ignition and youll get error led on dash.
- Does ECU codes implicate anything?

What I would do:
- Take a long screwdriver and use it as a stetoscope (one end on different locations on engine, the handle on your ear) to locate the sound. Figure next out whatsinthere?
- Next go to a Nissan service manager (or some able maxima man) for an educated guess. Should not cost a penny at this stage...
- Make the tests they suggest: compression etc. Repair as soon as suggested as there could [if] also be a mechanical problem that can ruin whole engine. Do not drive any extra mile until you get answers.

KRMaxima21

The oil was last changed in August. I was actually going to change it last weekend but ended up having to go out to North Carolina for some family stuff. How would I go about taking care of a sticky lifter if it is that ?

avmaldo

first just try the oil change, im not sure but i think the lifter gets sticky with older oil.

505max94se

iTrader: (15)

You should defintly change your oil. Lifters can go bad with dirty oil because the oil passages that feed them can get clogged. A lifter problem is also a very minor problem. It isn't something to worry about too much but, it can be annoying.

Is the noise worse when the motor is cold? Is the noise a clicking noise, rattling noise, or a clanking noise?

I'm not sure about the vg but, I used to have a 89 ford probe with a bad lifter noise and it was very easy to fix. I would think the vg would be pretty easy also.

Wiking

Some uncomplete thin kings:

First go and find out the actual cause. It might be smtg else, impossible to say online. If it is lifter, that does not most propably endanger your engine. But there are a lot of reasons for loud clicking starting from blown gasket piece inside cylinder...

You speak also of hesitation. Figure out how much is it: If one valve lifter is noisy and "half dead" you most probably will not find out that (8% pwr loss). If one cylinder is totally dead you lose about 18% power, thats smtg you 'feel'. If it is multiple cylinders, that could be whatever percentage. Then figure out the cause depending on that: If all cylinders loss power, what is common to all these?

Nissan might give you an hard answer if its lifters: "Open the engine, replace all lifter$$$$ ...But I suppose they will give an estimation of the problem its remedy and price - free, take it.

Then ask someone (here?) of another place in your area that could do better, cheaper.

If it is a lifter, one might ? change just the noisy one. That wisdom depends if it can be [dunno] replaced without opening the engine [by compressing that cylinder to keep valves up during lifter R&R], and if one (or more) lifters are bad and should be replaced. I suspect all reasonable mechanics say that change all lifters, but its your money. First of all, figure How long you will keep this car, engine, how many miles is on it, what else should be replaced etc...

Loe max

iTrader: (6)

Are you talking about your 1991 VG? Because they don't have VTC's and the sound your hearing might be exhaust studs

eric93SE

iTrader: (1)

Check to see if your temp sensor terminals are coroded. When I had the JWT ECU, that was my problem.

KRMaxima21

Well I sat and listened to the engine last night and tried to pinpoint the noise. It was coming from the crankcase and the harder I revved the engine the louder the noise got. I poured some Gunk Oil Detergent which supposedly helps free sticky valve lifters and after pouring it in the crankcase and letting the car run for 10 mins the noise is completely gone. My car actually seems to idle alot smoother now also. Saturday I'm going to change my oil and maybe do an engine flush.Is there any possible way for me to make sure this problem doesn't reoccur again ?

Wiking

"Gunk Oil Detergent" was a good idea. If this helped, I think youre free now as the gunk sits in the filter... Occasional oilchange helps.

If you had hesitation only on this one issue, then the oil system is full of gunk. Try to figure out why? Anyway, flush it well.



VTC noise -Originally Posted by Phatsta: I have the exact same problem-
- One article said that oil filters have different pressure charasteristics, and using other than Nissan genuine results in VTC click. Dunno, but that one is not expensive from Nissan, so why not use it.