cdumont1

I'm new to this forum and couldn't find any information that pertained to this problem I am having. I bought a 1999 Mustang GT automatic about 6,000 miles ago and i currently has 68,000 miles. In the last 2,000 miles there has been a ticking noise that has progressivly gotten worse and sounds like it is coming from the valves or somewhere under the intake manifold. The tick also accelerates with acceleration in the engine. I was wondering what the proper procedure would be for finding the the source of the tick and for fixing the problem? or any ideas on what it might be? I am a college student without much money so I dont want to take it into the shop, but I have a Haynes Repair Manual and I am pretty confident.

Other issues that I am having:
1. RPMs sometimes surge with throttle held constant (usually between 1500-2000 rpm in 2nd or 3rd on an automatic)
2. Then the engine seems to-I am referencing the Repair manual when I say this-ping or knock when engine is under load.
3. In Neutral, the engine accelrates smoothly up to 2000, then shakes a decent amount, and disappears after about 2100. Is this normal?

From reading the Repair Manual on possible causes of 1 and 2, the common cause seems so be "Fuel Injection or engine control systems malfunction." For 1, a possible source seems to be a vaccuum leak at intake manifold or vaccuum hoses, since many of the hoses seem a bit cracked. Another possible source for 1 could be "fuel pump or pressure regulator defective" since I have not replaced the fuel filter yet. As far as 2, it seems like it could be incorrect spark plugs. All of this i get as possiblities from the Repair Manual.

At little background on the car.
I bought it at 64,000 miles. Previously, it had sat in a guys driveway, outside, for about 2 or 3 years after his son died. His son was a drug addict, which does not say much, but leaves the potential for an irresponsible person to drive the car pretty hard. The car had not been driven much during the time it sat and a few of the wheels developed some rust, and the interior had some water because it is a convertable that leaked a bit. I stripped the interior and cleaned it and found some rust starting on many metal parts around the dash. Upon recieving it I replaced the airfilter, oilfilter, Mobile 1 10w-30, differential fluid, transmission fluid and filter, replaced calipers and rotors on all four wheels, replaced spark plugs, and radiator flush and fluid all done by myself. I then power washed the engine-big mistake- and had to take it for diagnostics after the car started running really bad. They told me the coil over plugs needed to be replaced and the spark plugs had carbon diposites and needed to be replaced. I looked at the spark plugs and they looked fine so I only replaced the coils.

I know this is a lengthy post butI just wanted to give all information that might pertain to the potential problems. Like the fact that it was sitting in a wet enviroment might cause some gaskets to crack in the engine? Thanks alot for your help and I any potential leads would be much appreciated.

Also, is 600 rpm standard idle in Drive on an automatic, and if not what is? Would replacing the oil with Mobile 1 5w-30 after 10w 30 be bad? Would taking the oil filter off and cutting it open and looking for metal particles tell me anything that might lead to the source of the tick?

fobra570

sounds like a sticking valve/lifter

i would pull the valve covers off c if their is no oil in the top end / any play on the lifters / rocker arms

GodAmGT00

First off, there are a few things that you can check that are free... First off, are you sure that you put enough oil in the engine?? A common mistake that folks make with cars, when they've sat for a while, is that it's a good idea to prime the engine w/ oil, prior to the first start... All of the oil passages will be bone dry, all of the bearings will be bone dry, and even the oil pump will be bone dry.. This can affect things several fold.. By the sound of it, I lean a little bit towards EFI system/Ignition being the culprit.. Vacuum leaks tend to be pronounced throughout the entire RPM range, and even when idling.. If you feel the lines are cracked and maybe could issues, replace them; they're not that expensive..

Power washing the engine is not the best idea, but I can understand why you might have done so..When you replaced the coils, did it have an affect on the engine?? Did you gap the spark plugs correctly?? Is there any dark smoke that comes out of the tail pipes when idling/driving? Carbon fouling could be a couple things, and a vehicle that sat for a few years, tends to develop varnish deposits, as the fuel separates.. I'm not saying that this is the absolute answer, but hopefully it can get you going in the right direction..

How many miles have you driven it since you've got the car?? Have you tried using and fuel system cleaners?? If not, try that, with a full tank of fresh fuel.. Run the tank out, fill up again, and if it is the fuel system just being dirty, you'll notice a bit of improvement within a few hundred miles...


JT

cdumont1

I got the car around 64,000 and changed the oil at about 64,500. I power washed it at around the same time and it caused the car to run very crappy. I dont know how to describe it but basically it was vibrating alot at idle, then it would not run correctly when putting the gas on, and by that i mean it was sputtering alot and what not. The guys at NAPA did a diagnostic and told me certain coils were bad and the plugs were bad. I then replaced the coils with Accels, and left the plugs which were double platinums. The car seemed to run fine after replacing the coils but I noticed the RPM problem a short while after. The problem only seems to arise though when I am not accelrating keeping the car under 2000 throughout acceleration (i do this to save gas). Since then I have check the plugs for correct gap and they seem fine give or take .02 since the tool I was using was kind of crappy. All plugs seemed to have normal wear. I also did use a fuel injector cleaner when i first got the car.
There is no carbon soot coming out of the exhaust. Another thing i forgot to mention was that sometimes when in idle, the RPM will all of a sudden jump up 100 and back down. This will happen at a dead stop in Park or Drive, and will usually when it happens, it does it every mabey 8 seconds. I have driven the car about 5,000 since I have had it for abouta year now.
I guess I will look into the EFI system and try and fuel system cleaner. Any ideas on where to start for checking EFI problem? I will also consult my manual.
Thanks alot for the help.

I also was wondering if it is possible to make a tire sidewall repair. I nicked a curb that tore the sidewall but did not puncture it. I have driven it like that for about 3000 miles and the tear has not changed. I appears mostly cosmetic but i was wonder if I can somehow glue the hanging flap down? or some other repair?

jtfrog

It sounds like the coils. From reading a lot spraying down the engine can cause this. As for the tire its toast, can not be fixed and I wouldn't drive on it.

GodAmGT00

The idle surge issue could be related to the IAC, which is a common problem with the 4.6's. It is possible that you may have somehow either got water in it when you were power washing, or you may have damaged one of the vacuum lines coming off of the IAC body.. I don't necessarily think that your coils were bad, merely getting them wet will cause them to malfunction.. It's good that there isn't excessive smoke or unburnt fuel coming out of the exhaust, meaning that you're not running overly rich.. However, what do your plugs look like when you pull them out?? Is there any whitish coating on them, or does it look like there's excessive oxidation on them?? It is possible that your engine could be running lean, meaning that your injectors may not be spraying accurately, or could be dirty. Your fuel filter may not be any good, or even possible that your fuel pump could be on it's way out....

I'm not even sure at this time, of ways to test your injector duty cycle or injector flow rates without either a scan tool, or having someone flow test them.. You can however, check your fuel pressure by getting a gauge, and following the procedures that are in your manual. This will help you rule out your fuel pump/fuel lines up to the fuel pressure regulator at the beginning of your fuel rail..

As for the tire, yeah, there isn't much you can do to save it, and depending on how deep it is, you may want to look into getting a replacement, since it can be fairly dangerous at highway speeds, once it heats up...



JT