Alright, changed the distributor and rotor yesterday. The inside of the dist looked to be in ok condition, the rotor was a little worn. Went out today and it's still ticking under heavy acceleration and still only in first gear..I'm disappointed after everything that has been replaced its still making the noise. I'll try new spark plug wires next I guess, and if that doesn't work I might just do the plenum gasket and get it out of the way. Any other suggestions would be appreciated.

 

if youve got some extra cash, since you'll have the top of the engine all taken apart for the plenum, get some harland sharp roller rockers. it could just be ordinary lifter noise.

 

If the insulation on your wires is cracked,spraying some tap water on the wires will increase the visibility of the spark. More effective if done in the dark. Also, make sure you don't have any wires touching or crossing. I can't remember the cylinder numbers, but I know there is a TSP on making sure that two specific wire must be seperated.

Have you looked into an exhaust leak, especially around the manifolds? This can cause a ticking sound, but is usually constant.

Why does it happenonly in first gear? That's the part I can't figure out. I would hold off on the plenum gasket replacement. That's an expensive and time consuming project and your tests so far seem to rule that out. You're getting some good advice here. Keep working at it and see if you can get it resolved.

 

I'll try some water in a spray bottle and see if I get any kind of sparking effect. I have an Air/Fuel ratio gauge that's just sitting around, I may hook it up to the first O2 sensor and see if the ratio goes very abnormal, but I doubt I'll find anything weird. I'm looking over the "Ignition System Cross Fire/Secondary Ignition Wire Induction", TSB 18-48-98 to be exact. I'll try this tomorrow, weather permitting. As far as replacing the rockers, if it comes to having to replacing the plenum gasket I will replace everything in the top end I can afford.

I have a road a few minutes from my house that's about 5 miles and very straight and flat that I did some testing on. The tick is definitely only audible on 3/4+ throttle and in first gear. In fact, I can basically keep the gas floored and it'll tick until the truck switches to second, never to be heard again. If I slowly accelerate, then hit the gas so it drops down to first, the tick can be heard once again until it switches to second. No other gears produce the tick, which is extraodinarily awkward. I can floor it in any other gear, and just hear the engine rumbling. I'm sure most of you can understand my confusing. It sounds like its coming from the right side of the engine, not from the left side at all. If it's not raining tomorrow I'll stick my camera in the engine bay and ride around.

Coincidentally enough, my friend who has a 2002 Neon told me his engine makes a similar(might as well be the same for all I know) noise, and he's learned to "deal with it" for the last ~25k miles. I'm assuming that it's not that bad, but abnormal engine noises make me cringe. I may drain a little bit of oil tomorrow and replace it with some MMO and just incase the noise is a stuck lifter that somehow, and for reasons I can't explain nor understand, decides to reveal itself in hard acceleration and only in first gear. I

 

Chris, I think it's the plenum gasket. Do you ever notice a higher than normal oil comsumption? As for the wires, if they are bad, you will really notice it on moist mornings after the truck sat all night and the wire got damp. At idle and low speeds the wirs arc until the truck warms and dries the wires out. Unless you are able to see the arcing at night, I would be so quick to change the wires out. To see the arcing, you can spray some water around the distributor wires and back of the valve covers. Unless it is so obvious, you really have to look to see the arc. I got a wooden stick and moved the wires around until I could see the are arc last week. It was a faint spark and was constant. I had to turn the truck off to actually make sure it was an arc. I would imagine if you didn't use a wooden stick and used a copper pipe to move the wires, the arcing would be noticeable two ways: 1) a light blue arcing from the wires to the engine. 2) the less disireable way,



My guess, if the plenum gasket has not been changed, its a leak in the plenum gasket. The description fits a leak.

 

Cylinders 7 and 8 are especially prone to cracking
on Magnum cylinder heads.

The sharp edge of the crack
usually in the ridge between the intake and exhaust
valve seats can cause pre-ignition
when the sharp edge of metal begins glowing red
hot during hard acceleration.

It might be worth doing compression tests
or 'leak down' testing to rule this out.

To find which one of your eight cylinders is making the noise
you can either use a 'fuel injector test light'
(also commonly called a 'noid light)
or a 'fires in oil' sparkplug sleeve
both of which can be bought cheaply.

Disconnect one fuel injector at a time and plug in the noid light,
or unscrew one sparkplug at a time and put in the oil sleeve between the sparkplug and cylinder. Do acceleration runs and listen for the run where the noise goes away.

A broken spring or rocker arm or bent pushrod will make a noise like 'ping' when the rpm gets high enough....the noise happens when 'bounce' starts getting really bad.

 

Thanks Hank. I'll give the sparkplug sleeve a shot and just keep trying until the sound goes away. I'd much rather have a blown plenum gasket than a cracked cylinder head, however . I was going to give the water spray a shot today but it's been raining all day, and while rain doesn't bother me, 30 degree 'freezing rain' is quite annoying. In Charleston we don't get 'snow' persay, the low laying air gets just cold enough to freeze rain before it hits the ground, resulting in a liberal peppering of bb-sized rain pellets.

Hopefully tomorrow it will be a little less rainy and I'll have a chance to get out there again. All the help thus far is very much appreciated.

 

Ok, I couldn't seem to find a spark plug sleeve anywhere but got my hands on a injector testor. The tick/ping stoppped when the light was hooked to the #8 cylinder, and I got really excited..until I tried it on 2 other cylinders (#1 & #7) and it produced the same effect. Couple more just for giggles and it seems the noise stops when atleast one of the injectors is not hooked up, not matter which one. This is driving around the block a couple times, hitting the gas a couple times, and coming back home. Hooked them all back up, and the pinging returned. I hooked a pressure gauge to the pressure valve on the driver's side and it's 47-49 psi, on idle and under any type of load. I haven't been able to verify from the forum if this is abnormal fuel pressure.

Also sprayed some water on the wires earlier(dark outside) to find no arching, though changing the spark plug wires is something that'll make me feel better, even if they aren't causing the problem.

 

Upper 40s for fuel pressure psi is good.

When you are driving at 'part throttle' and have one fuel injector disconnected and on the tester
that cylinder is pumping unburned air into the exhaust
and the O2 sensor is being fooled into thinking your air to fuel mixture
is too 'lean' or having an excess of oxygen. The PCM computer then
richens the mixture for the remaining 7 cylinders, which reduces or eliminates the pinging and detonation.

At foot to the floor 'full throttle' engine operation,
the PCM computer quits reading the O2 sensor
and uses pre-set values from its internal memory
to run the fuel injectors.

It sounds like your Hypertech is using so much ignition advance
that you are getting pining.

What to do?

Use higher octane gasoline like the Sunoco 96
or experiment with 'custom blending' in some 105 octane E85
to your daily use fuel.

Try gapping the 3923 sparkplugs small, like 0.020 inches

Try the crankshaft position sensor mod to reduce the timing.
You can get 1-3 degrees by slotting the mounting holes
but the sensor is VERY SENSITIVE to the gap between it and the flywheel notches.

Only drive the truck when it is very cold ;(

Take the Hypertech off and sell it.
Use the money toward a future purchase of a Megasquirt or a FAST aftermarket PCM.

 

if you have any oil pooling on the bottom of the intake, your plenum is leaking and needs to be fixed. As Hank mentioned the heads are prone to cracking, however on mine when I yanked them it was spread across 3 on 1 side & 2 cylinders on the other side. another possiblilty for your ticking is a collapsed lifter or one that is not pumping up all the way. I suggest adding some marvel mystery oil to the crank case to clean the motor out since the truck is fairly new to you. I personally had a lifter that was not pumping up all the way, the MMO (12 oz of it) fixed it. others have tried it and did not have success.I didnt read thru all of the posts since my last visit so if this was covered, sorry for the repeat.