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New to the V8 club!

2K views 33 replies 7 participants last post by  Mugeismo 
#1 ·
Hello everyone. Finally joined the V8 club today. 99 GT convertible with 150K. Body has the usual dings and dents but zero rust. Top needs replacing and the interior needs to be converted to black. Engine is currently backfiring after sitting for a winter. All in all though, still well worth the $1000 I paid. Finding a rust free Mustang in Michigan is virtually impossible (I know, my 11 has more rust).

So since the engine is backfiring, I figured I would check here first. This is my first true domestic project, but I'm guessing most things are the same. Just a matter of shape, size, and where it was put.

I was told to check the following:
1) EGR system not functioning properly
2) Ignition timing incorrect
3) Vacuum leak
4) Damaged valve springs or sticking valves
5) Vacuum leak at the intake manifold or vacuum hoses

I'm going to replace the EGR valve just because it's cheap and easy to do. However I noticed something funny when we were loading the car onto the tow truck. He had the MAF disconnected. I asked why and he said the engine won't idle unless it's unplugged. So I figure, why not replace the MAF when I replace the intake? They tend to go bad and then really screw with A/F ratios.

I know he recently replaced the plugs and coils. So I'm going to rule those out for now. I'm also going to have the timing and catalytics checked. Plus I'll replace the fuel and air filters.

Just curious what others more experienced with this engine think.
 
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#4 ·
I agree. That's why the plan with this car is so simple. I'll still keep building my V6, but it's not gonna see any new mods for a while. I'm debating just replacing all the vacuum lines. However after spending an hour in the engine bay last night I've come to realize this car has less rust on it overall than my 2011 does...and it's in good shape.

End goal:
- Engine running reliably
- New interior (minus rear seat)
- New top
- Long tubes
- Catted x-pipe
- Exhaust dump
- Intake
- Tune
- Airlift suspension

Change the pcv valve. Use a motorcraft one not a universal one
Thanks for the heads up. They're only $5 so why not?
 
#6 ·
Picked up an OEM PCV valve and grommet for $10 through AM. Local junkyard has an MAF for $25. I'll probably grab an AutoZone special EGR valve while I'm at it.

Jump the battery, force reset the PCM, and cross my fingers.
 
#8 ·
Make sure the PCV valve is a Motorcraft brand. Some of the OEM aftermarket ones do not work well with high mileage vehicles. We had some idling issues with one of the aftermarket OEM ones.
It is definitely a Motorcraft. If I can afford it, I'll always go Motorcraft for parts. I also picked up an MAF off a Continental that is supposed to be the same. I'll test this too since he was claiming it was bad. $25 and I can return it if it doesn't work, why not.

I plan to reset the PCM, swap in the MAF, and see what happens. Then I'll replace the PCV and see what happens. Then I'll swap in the EGR. May as well swap one at a time to see if that directive part is the problem.

Not sure how to test the vacuum lines, but under the hood is dirty yet as about free of rust and wear and tear as I've ever seen.
 
#13 ·
Well the good thing is I already made a backup of my stock tune. It's on my computer. Granted I would still have to ask SCT to reload it if something happened since it's a different file format (I'm assuming to prevent tampering). I will see if anyone I know has just a regular scan tool I can use.
 
#18 ·
I haven't gotten a chance to check codes yet, but I will this weekend. Someone pointed to possible fuel starvation as the reason for the limp. Going to check my fuse, relay, and inertia switch. Then drop the tank to check out the fuel pump. Injectors may also need inspecting. Oh the joys of old cars.
 
#19 ·
I applaud your willingness to tear into stuff, but there is much better/easier ways to check pump operation. Like pressure checks, datalogging etc. Do a search and save yourself time and money and back pain LOL. I hope nobody mentions it might be a crankshaft problem and you tear the engine down, just kiddin but you get my meaning, save the eventual frustration and try to troubleshoot first.
 
#20 · (Edited)
I get your point. I know the limit of what I can accomplish in my garage with simple tools and a jack. Beyond that, I have to go to an expert. My time, tools, and skills are limited. Proper diagnosis beats speculation any day.

The backfiring I tried fixing based on the Chilton manual. I swapped out the parts that I could, but didn't check the vacuum lines or intake/exhaust valves because that's out of my range.

The fuel starvation I tried fixing based on what fuel components could be easily checked. Since I can get to the relay, inertia switch, coils, etc easy I figured why not check them. Checking the pump, sending unit, etc is out of my range.

Ultimately I know I need to get an expert opinion and have the car looked over fully by someone with the right tools and expertise. My goal for now is to swap out the simple stuff like the EGR/PCV valves and more that just simply need to be done. Given the age of the car, there are a lot of things I want to simply replace just for peace of mind.
 
#21 ·
Don't trust that the coils and plugs were actually done and done right.


Half the time ppl use ebay coils and don't torque the plugs properly.


But... the backfiring could be any number of things. Coils and plugs, MAF element needs cleaning... something BS like that or it could be a leak somewhere or something serious with the engine. The good news is that Vic/Marquis/Towncar engines are dirt cheap and a 100% direct replacement.
 
#22 · (Edited)
Don't trust that the coils and plugs were actually done and done right.

Half the time ppl use ebay coils and don't torque the plugs properly.

But... the backfiring could be any number of things. Coils and plugs, MAF element needs cleaning... something BS like that or it could be a leak somewhere or something serious with the engine. The good news is that Vic/Marquis/Towncar engines are dirt cheap and a 100% direct replacement.
I'm still amazed at how much cheaper/more plentiful parts are for the New Edge versus my S197. Eventually I may trade my V6 for another New Edge.

I got so close to trading my V6 yesterday for a 2004 Mach 1 with 20k. The car was in pristine condition and #2 on my must have list. Unfortunately they wouldn't come down from $17,900.
 
#24 · (Edited)
It is, but considering the miles and pristine condition it was worth it. I offered 16 even but got shot down.

In other news, I'm selling the 4.6L and 4R70W from my car. I have no interest in dealing with modulars. I also sold my V6. I'll startup a new thread soon with the swap info after this weekend's teardown.

Side note: never could pull codes from the car. Battery was disconnected for so long I got P0001 and it wouldn't run long enough to cause a code.
 
#25 ·
Why no interest in modulars? They are the "new cheap foxbody" except without the paper mache block and stock heads that can support a lot of power.

Sent from my LG-LS997 using Mustang Evolution mobile app
 
#34 ·
Thanks. Compared to some of the Nissan and Honda builds I've done, this doesn't feel all that ambitious. I say that now, but I'm sure that'll change. After you've done a few full front-clip swaps it's easy to be confident. The joy about Michigan is that we have about 6 months of winter. So plenty of time to do the grunt work involved in this build.
 
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