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1997 3.8l slug

2583 Views 23 Replies 8 Participants Last post by  JonR2006
Hey Everyone! I'm new and this is my first post. (So be gentle when telling me all the rules I'm breaking in this post.)

My first car I ever had was a 1997 volvo 960. I kept it around, even after getting my 2011 Fusion, and even after trading that in for the 2014 Fusion. Finally though, the 960 bit the dust. Not sure what went wrong with it, but I'm not going to be that concerned with an 18 y/o station wagon. So I went and bought a 18 y/o 3.8l mustang. It was cheap, and it has it's problems. I plan to turn this into a project. First I want to get it running properly. So here is it's current bill of health.

Differential has a leak (Not sure on severity, I see where fluid has been seeping down the housing.

Transmission has slight leak. (O/D light flashes intermittingly)

Main Seals slightly leaking, front and back.

passenger shock, tie rod, wheel bearings, and ball joint needs replacing soon. (That squeaking is like nails on a chalk board)

And now for the fun part.
It drives like a slug, Like first gear doesn't even exist to this car. Come to find out, it doesn't, Shifted down to first (Auto Transmission) and it acts like a break. But the car will go, just feels like it is taking off in second gear. Also, the car struggles to go over 60mph. Pushing it too hard gives you a flashing O/D off light. I've checked the transmission fluid, and it looks very clear (red) and clean, but I'm no mechanic.

The previous owner cut off the second catalytic converter on the drivers side (Because it was glowing red). Now I have replacement to go on it soon, just need to find the right muffler shop to weld it on.

The car will idle at about 1600rpm in park or neutral, but drops to 600 - 700 rpm in drive. I'm not sure what is normal for this car, but it sounds weird. There is a slight vibration, and slight popping from the exhaust. Not sure if it's cause I'm sitting on top of a cut muffler, or if there is a bigger issue at play.

I'm no mechanic, and I don't pretend to be. But I want to get into this as a hobby and I think a mustang is a fun place to start (Sure beats that station wagon). I'm a software engineer as a profession so as far as time goes, I'm really limited to just weekends to work on this.

So, Where do you guys suggest I start? How do I solve the sluggish accelerations? Do I replace/rebuild the transmission? Is the cut muffler causing issues, should I wait to see what happens after that is fixed? Should I just weld on the one cat, or replace the whole Y pipe? Should I go cower in the bed and sulk over the few hundred dollars I spent on this salvageable ride, or is there hope?

I've already flushed the power steering system (black and syrup like)

here are my goals
  1. Pass state inspection due in 01/15 (Texas - Emmissions requirements)
  2. solve sluggish accelerations
  3. fix body damage (Did I mention it's been in a wreck before? frame is still good!)
  4. ...
  5. Become Guru Mechanic
  6. Replace main seals
  7. ...
  8. v6 to v8 conversion
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Texas emmissions is easy to pass.. honestly my v6 passed and you can pass as long as your engine light is off and the moniters, but two, are ready. Sluggish acceleration is probably due to it is a 97.. v6.. producing a whopping 145hp from.factory. plus the missing cat.. does Not help. Lack of back pressue screws the v6 in the performance of the motor. I personally would, if you have the money, get a the cat fixed and get it plummed for dual exhaust. Flowmaster 50 series mufflers so it can sound simi stock. Unless you want it louder then go with the delta 40 series. Mid pipe doesnt matter just preference between h or x pipe. Transmission.. thats sketchy.. if the owner before you "fixed it up" then id probably change the filter and fluid with proper mercon V fluid. 14qts to fill it. If that doesnt help then id suggest you find a transmission guy to inspect it. The main seals... those are toast. Id service your transmission fluid the same time you do the rear main seal. Front seal youll need a harmonic balancer puller. Differential leak could be the rear cover gasket or possibly the front oring, I believe, leaking. If you also want a quick boost of HP out of that v6 change the upper and lower intake out to the 99-04 v6 mustang intakes. That should get you an estimated gain of 50hp. Suspension is fun to do on this car.. the rear shocks of course are butter.. tie rods are alright.. wheel bearing simple enough and the ball joint... ouch.. anything else you have questions about respond id love to hear how.. fun this car will be for you. hah good luck!
Also almost forgot to add, do a tune up and change the oil with some gold valvoline or Castrol, high milage if you need it, with a motorcraft filter. Fl-400s I believe is what your v6 takes. Walmart sells oil pretty cheep. You can get away with a 5qt jug and a filter for under $30. Plus its the perfect size for the motor. No need to measure, just dump and go. For the plugs I'd also recommend motorcraft and BWD wires if you have to get wires from the auto parts store. And on the gaskets, I trust felpro for everything on my car. But do what the budget allows just dont go too cheep or youll regret it in my opinion.
If your missing a cat and the pipe for that side of the exhaust ends there that can play a huge role in your sluggish acceleration issue. I have a 98 v6 (well it's more like my girls car) and it accelerates very nice. All it has is a cold air intake to help with that and that isn't even doing much if anything at all. Also if the catalytic converter was glowing hot that's a good indicator that it might have been running rich (on that side at least) and the cat was being fed more unburnt fuel than it could handle this glowing red hot.

The high idle is definitely an issue. 600-800 should be fine neutral or in gear. I'd check for a vaccum leak. Fairly easy to do. These cars have a smog pump(designed to operate only during the first few minutes of a cold start to reduce emissions only) that adds to more potential vaccine leaks so check that out too.

I also advice cleaning the MAF sensor. Your local auto parts store has a spray bottle specifically designed to clean the MAF(Mass Air Flow) sensor, just follow the directions. You didn't state your mileage on that engine but I'm assuming it's been around quite a bit and a dirty maf will give you poor mileage, bad idle, sluggish acceleration, or even high idles as the engine cannot get the correct readings of how much air is entering the engine and can't inject the correct amount of fuel.
I've seen many cases were the MAF is dirty and causes issues without throwing a CEL.

For the transmission, like stated above, I'd replace the fluid and filter along with new seals. This v6 I bought had the wrong type of oil when I bought it, flushed it out and added the correct one and it's a lot smoother. The flashing O/D can be a number of this but most commonly it can be a bad solenoid. I've had Hondas that had the same symptom, no first gear, sluggish acceleration, come to find out both were caused by a bad solenoid. You can search here or YouTube on how to troubleshoot a solenoid to see if that might be the issue.

And welcome to the forum by the way!
I'd reconsider making a project of that car . You'd be far better off starting with a v8 car . Far more aftermarket support for the modmotor , lots of used parts available for pi / forced induction / or 4v swaps .
First of all, Thanks everyone for the comments.

Update:
Just finished a tune up and found a few things that may explain quite a bit.

First of all, the odometer stopped working at about 171,502. So I took the gauge cluster out to have a look. Almost like what you would see in a cartoon, the gear that drives the odometer poofed to dust as soon as I touched it. I understand this is a common issue with these cars however. But while I was in there I notice alot of lights were missing from the indicators. So in a round robin sort of fasion I moved around some indicators. So as it turns out the check engine light is on. Whats worse... It's flashing facepalm2.gif

I immediately started a compression test and found the following
Cylinder 1: UNTESTED
Cylinder 2: UNTESTED
Cylinder 3: 125 psi (Dry Test)
Cylinder 4: 30 psi (Dry Test)
Cylinder 5: 30 psi (Dry Test)
Cylinder 6: UNTESTED

Anyway. with this upsetting news I pushed forward with the tune up. New plugs, spaced to .054 and new wires provided by Bosch. New oil filter and oil (Valvoline MaxLife high mileage) replaced the PCV valve (Which looked like it had never been touched)

Now that this has been done, the engine does sound a bit better and it isn't as rough with the idle any more. Whats more, the check engine light isn't blinking any more. But I know this doesn't fix the compression issue, and it's still a slug, though not as bad. The side of the engine with low compression is the same side missing the catalytic converter. But I'm sure that's more of an effect of the misfiring that caused that.

Also, plug 1 came unconnected while test driving after the tune up, but it never stalled. It did rock the car quite a bit. Kinda scary. Plugged it back in and it went back to running as it was right after the tune up.

So, with this new information, what do you guys suppose I do. Keep in mind I purchased this car so that I could learn to work on cars. before this you would hardly find me under a hood. (Now I've learned to double check the connection on the plugs...)

What do you think is causing the low compression? Is It possibly a blown head gasket? or is there something less terrifying?

if it is the head gasket, should I rebuild the engine? or drop in a v8?

Is this probably causing the transmission issues?
Its your call on the motor. You could pull the heads off and valve covers to do the valve stem seals as awell as head gaskets. Or what ever you want. I have a 02 v6 that I decided to build up. It produces right around 249rwhp. About as much as a 4.6. In my opinion it is more fun to build up a motor than buy a New one but it is cheeper and simpler to do the motor swap
I also found out that if you planned to do the split port swap youll need a little more parts than expected... https://www.v6mustang.com/threads/sixpackstangs-official-split-port-swap-post.95288/ here a site I just came across due to another thread stating it.
Thanks!

I did a wet test on cylinder 4 and the pressure stayed at 30psi, but while I did this i think I noticed a crack on the head, so looks like I'll be at least rebuilding the top end of this engine.

So here's a question. What is the engine block made of on this car? Is it cast iron?
I believe the block is cast iron and the heads are aluminum.
It would be a better idea to do a leak down test on all the cylinders to determine if its the head gasket, piston rings or valve seals that are bad. More than likely you will have to rebuild the engine and that can get pretty expensive. You can find the 3.8l engine at junk yards for cheap ( around two or three hundred) if you can pull it yourself that would be a cheaper way to go.
I do not think that you will have to get a whole motor. You can probably get away with new heads and gaskets. But if you have some extra dough laying around hit up SuperSixMotorsports and look into getting a cam, rocker arms, springs, and pushrods :D estimated 1500 dollars with gaskets. If you are intrested I can find the part number for the rocker arms. It is cheaper to not get it through him.
Okay Provide the part numbers, see if i can get it all under $2k =) I'll post pics and vids of replacing the heads. Too bad though, that was money I had set aside for body work. Guess it will just wait until next year.
You got way too much other stuff to fix first before buying a fancy top end kit. Get a used junkyard motor from a 97-98 as they have the revised head bolts. Get something with reasonable mileage with a warranty and I bet you'll spend under $500. Do the install yourself and another $200 in fluids later you're back to having a properly running car with $1300 to start fixing all the other headaches. SSM will want cores and it sounds like your cores are junk meaning your upgrade kit will cost more in the end.
Rocker arm part number is 1619-12. Summit racing carries it and amazon does also. 240.01 it seems. They come with nuts but the one SSM carries is the correct one, I know when I did it the nuts supplied wouldnt work and I had to hunt around everywhere to find them. But if that digs into your body work funds I wouldnt worry about it that much. The mods are definitly fun to toy around with. As long as you dont delete the egr you should be able to run the car for awhile and it run fine. My car had only codes for egr. Ran like a turd, alittle rough with the idle, but it still got up and went. A tune defintly helps, I'd go through American muscle for one. But as long as you dont have the inspection anytime soon id do it. When I did my mods my inspection expired the next month, so I rushed to get my car tuned and it passed with the help of bama only. Good luck with your car, hope you enjoy it.
I'm putting my money on just bad heads due to overheating at some point. Most likely the valves are not functioning as they should.
Lefty is right, The heads are warped. I'm giving the dealership a 3k budget to rebuild the engine and do as much maintenance as they can. This blows the body work budget. Guess I'll handle that next year.

Say... Is it worth it?
If you are going to do that id go ahead and also change out the driver side valve cover pcv baffle to the 99-04 style. 94-98 are notorious for oily intakes. Either way it will still be a great daily. From rock auto you can order yourself a reman block for 2 grand. Id look into that too. Unless you wanted to modify it alittle. The reman from rockauto would be factory original. Good luck! Keep us posted.
You could part that car out, and put the 3k towards a new edge GT....are you stuck on keeping this specific car? You could even find New Edge V6 for 3k in decent shape....
Lefty is right, The heads are warped. I'm giving the dealership a 3k budget to rebuild the engine and do as much maintenance as they can. This blows the body work budget. Guess I'll handle that next year.

Say... Is it worth it?
Well, older cars in general are rarely worth the money. A 3 thousand dollar engine fix is not technically worth it and it's better just to drop a lower mileage engine in there (especially a V8 if the power matters to you), but if you have some sort of attachment to the car, by all means, go for it. I had an '84 Cutlass in fairly good condition that was a bit of a money pit (had body work done and rust came seeping back through somewhat; had some frame rail rot) and the 305 had no balls whatsoever, but man did I like the car.
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