is it really this slow?

[331strokerlx]

bad news. lately the motor has been making a noise when it is under a lot of load going up hill and it sounds like something knocking. It only does it in third gear when there is load on the motor. My stepdad thinks it might be a crankshaft bearing. If that is the case is the motor a ticking bomb?

 

[Gearbanger 101]

Knocking under load is usually attributed to rod knock, but in any case, it doesn't sound ideal. I would be pushing it to hard unless you've got something else on stand bye.

 

[LaserSVT]

That is the reason you spend money on a tune when modifing a car, so you dont blow the damn thing up and kiss all your hard earned cash goodby.

Tune will adjust fuel and timing curves. If you ran it too lean you may have knocked a hole in a piston or dammaged a wrist pin or connecting rod. Bad timing setting could have caused detonation and in addition to the other things I listed you could have also bent/dammaged the valves and push rods.

Spinning a bearing would be from over-reving, over-heating or under-oiling.


Now you may not have rod knock or bearing noise if its only third and only a slow accelerating load. It could be pinging and if its loud enough to sound like rod knock then you may have already dammaged the engine but if you didnt I would check timing and fuel components. What is the base timing set at? What mods? What fuel octane? Last time the fuel filter was changed? Fuel pressure?

 

[331strokerlx]

the timing is set at 12 degrees. I always run 93 octane and the fuel filter was changed 2 weeks ago. Fuel pressure is set to 39psi at idle. As far as mods it has trick flow street heat intake, bbk equal headers, msd distributor, 76mm maf, 30# injectors, pro products throttle body not sure of size,off road h pipe and was told stroked to a 331.

Should I try a different octane of gas?

would it be easier and cheaper to rebuild the motor or swap in another 302?

Could it possibly be an exhaust leak?

 

[kevin2m4]

subscribing, personal similar story.

 

[LaserSVT]

Try backing the base timing to 10*, prolly wont help as it may very well be internal dammage but its worth a try. Do you think you can get a recording of the sound?

 

[Mr. Rustypwnz]

another thing to try is drain the oil and see if anything comes out. if anything metallic looking comes out with the oil I would be looking for a new bottom end. I bought an 86gt from someone on here. and he said it had motor work but really didn't say everything in detail. the car ran strong. but one day I had a roller rocker fail and some needle bearings got in the oil pump. long story short I still have some pieces of the engine. its very expensive but can be a steep learning curve for the better. just whatever you do don't beat on the car. diagnose what's wrong now and save yourself a grand later. where are you located? maybe a stangnet member could help ya out.. kinda sounds like the trans is going.

 

[Mustank]

Why did you keep beating on your car when you knew it had problems?

You might now just be learning the proverbial "hard way"...

You still never said wether or not you changed the shifter and worked out the transmission problems.

You said earlier that it struggles below 2500 and bogs down in 3rd/ doesn't accelerate past 3500 - to me, that sounds like you're in Overdrive. Maybe your shifting from 2nd to 3rd to overdrive instead of 1st to 2nd to 3rd. You said you can't manually force the car to start in 1st, right? That probably means your shifter is off. Your 2nd is probably "Drive" and your "Drive" is probably OD...

You also said earlier in the thread that the fuel pressure dropped when you revved the engine - was that just a fluke, or did that problem go away with the fuel filter swap? Maybe you should check again to make sure you aren't losing pressure under load.
Do you know what kind of fuel pump you have?

Have you dumped the codes?

Also - If the knocking only happens in 3rd....are you sure the sound is coming from the engine and not the transmission?

 

[331strokerlx]

I dont beat on the car all the time like you guys think. Other than when i was at the track I take it easy on the car. i got the shifter thats in the car tightend down so now I can get the car in first manually. I counted how many times it shifts in drive and it always shifts 3 times until I put it in od. The fuel pressure doesn't drop anymore since we changed the fuel filter and adjusted the fuel pressure regulator. I havent dumped the codes yet. Is that something that autozone can check for free.

I will try to record the sound later.

 

[90lxcoupe]

yea autozone will do it for free

 

[25thmustang]

Is this your DD or only car?

 

[331strokerlx]

i went to autozone and they said that they cant check the codes because it is obd1. And the car is my only car

 

[90lxcoupe]

my autozone has run my codes before

 

[Mr. Rustypwnz]

cue JRicker with the codes writeup. pulling codes is very simple. i cant find the diagram to show you as im not on my comp. but you basially count the number of times a light blinks and look up the code for that number.

 

[5.0Droptop]

You can buy a code scanner at autozone and it comes with a book. I think it is around 20-30$ and its worth having.

 

[25thmustang]

If it's your only car I think your idea of avoiding the track and trying to get codes and fix it is the best idea yet. Only bad things will come from racing a car that has issues.

 

[331strokerlx]

would an easy way to fix the problem be going to 50resto and buying the economy short block and transfering the rest of the parts from my motor to the new one? or would I be better off just rebuilding the motor thats in the car

 

[86turbo]

I wouldn't do chit until you are absolutely sure the noise is from the bottom end. I don't think it is..

Drew

 

[LaserSVT]

Dude, you are welcome to bring it to me and I will check it out but I would hate for you to drive all that way on a spun bearing or bad rod. It may leave you stranded. Try and get a recording of the sound and put it up. May be something simple and if I feel it wont strand ya then maybe I can fix it for you.

 

[cobra1540]

If you put the car in park rev the engine to 3,000 or so ( not much higher ) . Let off the gas and you hear a knock as the engine returns to an idle, you have a bad rod bearing. If it knocks only on a cold start, you could have a collapsed piston (skirt).

With the engine off pull your intake elbow off the throttle body and have someone else push the gas pedal to the floor. Check to see if the throttle body is opening all the way. I've seen two aod's mustangs that weren't fully open.

You don't need a code scanner to read any hard or soft codes on your car. If you look in the driver's side of the engine compartment by the firewall. You should see a plug ( the self test output, it should have a cap over it ) that has 2 connections (top ) and four connections (bottom).

It looks like this :
` _ _*
_ _* _ _


All you need to do is put a paper clip, wire or needle nose pliers in the top right and bottom second from left spots. Then turn the ignition to the on position. The eec will run a self test and the MIL light ( Malfunction Indicator Light - check engine ) will flash any stored codes. There will be a two second pause between digits and a four second pause between codes. You may have to do this more than once and you should have the engine up to running temperature before you stat the self test.
The are running tests you can perform as well.