Okay, first off, this one's gonna be a long one guys. I've got more problems than I know what to do with right now, and I figured I'd just put it all in one thread.
So a little back story first. I got my first 'bird in I believe November of '09. $400 for the thing with a seized 305. took me a long time and a PITA engine swap for another 305 to get her going. Learned a lot in the process and I learned to love 3rd gens. Well, I realized this car was never gonna be quite what I wanted, so I shopped around and picked up a 91 formula 350 that was, at least as far as I could tell, running and driving well. this was my dream car, so I took her home with me. paid a pretty hefty price for her (3k) but the body was straight and I figured she would last a while with only 120k on the clock. Well, I lost my job, and I decided 2 cars was impractical, so I sold my little beater 305 about 2 months ago so I could have the money to fix up the little problems I had with my 350 and get it roadworthy.
Couldn't have made a bigger mistake on that one. Ever since I've been driving the 350 it's just been one problem after another. steering column went to **** literally about an hour after I sold the 305. finally got that fixed. new tires, and today got my new exhaust finished. Took it for a test drive afterward, and it sounds great, but my mom who was following me says she saw blue smoke coming from the pipe. Lucky me. So now I have a bad feeling I'm gonna be looking at a nice engine rebuild for this car. and thats just the latest and greatest problem I've noticed since I bought it. With over $4200 and counting sunk into it now, I'm in this for the long haul. So here goes.
1. Like I said, the engine is obviously worn out with blue smoke coming out, and the oil pressure reading somewhat low. I was hoping that it was just the sending unit, but that's not looking likely anymore. I'll be looking into that more at some point. But I've got a bad feeling that I will either be rebuilding or replacing at some point in the near future. I'd like thoughts on either a good rebuild kit, or a good crate motor at a decent price.
2. Trans fluid is darker than I would like. Was going to get it flushed, but I was told that that might be a bad idea, because new fluid in a tranny can actually destroy it. It shifts great and has no burnt smell, just darker fluid than it should be. Would like thoughts on this. Flush or no?
There's a list a mile long of other stuff that needs to be done (a/c, heater, loose/unplugged wires, possible vacuum leaks, minor leaks and creaks) but those 2 are the big ones right now . that blue smoke from this morning pretty much trumps anything else. So I guess thoughts on that stuff is what I'm really looking for at this point. If I come up with anything else I'll post it on here, because you guys have always been great helping me out with my cars.

 

Before you spend a bunch of money on a rebuild, do a compression check on all the cylinders and also put a vacuum gauge on it. Your blue smoke could be as simple as bad valve seals, which I would bet need to be replaced, if they are the stock ones from 21 years ago. If compression is good on all the cylinders (all 8 within 10%) and it is making steady, good vacuum, you probably don't need to rebuild it. DO NOT flush the tranny drain and pull the pan, swap the filter and Refill with fresh fluid. If it shifting good and doesn't smell burnt it should hold up.

 

Thanks for the response. I'm hoping for it to be something as (relatively) simple as a valve job... is the vacuum easy to check? I've never done that before. I'm taking it to a self-service shop tomorrow to check the compression and oil pressure so I'll just do the vac check then too. I was also told today by the guy who did my exhaust that it sounds like I've got a misfire in one of my cylinders. If I see low compression, can that cause a misfire? and if not, what else should I look for that causes it?
And with the trans, have you ever done that drain and replace yourself? I thought of that and I was told that even that might be a bad idea. just wondering.

 

I don't believe low compression can cause a misfire. But if oil is getting into the combustion chamber the oil could cause the plug not to fire, or burnt oil deposits could keep the plug from firing as well. Oil could be getting in because of bad rings or bad valve seals, seals are a lot easier to replace. Vacuum is easy to check you just plug a vacuum gauge into one of the numerous vacuum lines and read the gauge. http://www.secondchancegarage.com/public/186.cfmThis link is very helpful just click on the different scenarios and you will get a visual of what it should look like. The oil gauges on these cars are not that accurate so hopefully that is why your oil pressure reads low. Changing the the trans fluid and filter is easy, I just did mine last weekend. Put the car on jacks, put a jack under the trans to remove the cross-member, pull all the bolts (trans fluid will start running out, it is messy) pull the pan, pull the filter straight down, the o-ring will probably stay in the trans (pry it out with a screwdriver) install new filter, reinstall pan with a new gasket, torque the bolts to spec, install the trans cross-member and fill the fluid back up.

 

Now that I think about it, im curious, what is an aceptable oil pressure? Maybe I'm freaking out over nothing. At warm idle, it sits around 18-20. At rev it goes up to 45 or higher. Is that pressure at idle particularly low? Thats what rlly scares me because im pretty sure in my 1st bird, it would idle around 25 to 30.

 

I just changed the plugs, so hopefully thats not the problem. What would a misfire cause exactly? I havent heard anything particularly strange. I thought a misfire would cause pretty noticable problems. Ill post tomorrow after I take it to the shop and do those tests

 

did you inspect the old plugs? much can be learned from the condition of each plug. ideally when you pull each plug you should look at it then. this will tell you about the burn condition in each cylinder.

http://www.4secondsflat.com/Spark_plug_reading.html

 

They for the most part didnt look bad. I did notice when I pulled them that there was def oil on some of the threads though. And I do think my valve covers are leaking. Could it be that simple? Just oil getting into the cylinders from the valve covers leaking? That would be pretty cool

 

if the oil is only on the insulator end of the threads maybe. if its on the electrode end it's probably coming from inside the cyl.

 

Well im gonna have the new plugs out in a couple hours to do a compression check so ill take a look at them then. Might be a little more obvious whats going on on newer plugs

 

Good luck on your compression test. hopefully just valves dripping oil. make sure you let us know how it turns out.

 

couldn't get to the compression test today. didn't have a short enough plug puller to get past the stupid headers lol. I did finally figure out the engine light ive been seeing though. code 13, o2 sensor. strange, because i just had it replaced when the exhaust was done. Thought of another problem I've been having, so I thought I would throw it out there. You guys been helping me out a lot so far.
When I drive, especially when I am going at a slow speed, like backing out of a parking spot, my car seems to idle really strangely. I've had it die several times from this, but for the most part, when I tap the gas to back out, it revs then drops waaaay too low. like from 1000 when I tap the gas, then drops to around 200-300, shakes a bit, then back up to 600(normal idle). idle also seems a little rough when parked at say a stop light, but not particularly bad. car doesnt throw any codes other than 13, and so far trying to fix this Ive replaced cap & rotor, spark plugs, fuel filter, and checked timing. any thoughts on that? I've got a feeling this one's gonna bug me for awhile but I thought I would throw it out there and see if anyone else had similar probs

 

I had to buy a special socket from summit to get the #1 plug out with my AFR heads and Edelbrock headers. Your code 13 could be from an unheated o2 sensor. If your 02 sensor isn't getting warm enough, it could the culprit. You may need to get a heated 3 wire 02 sensor. Also you may want to check your base timing, TPS, and IAC.

 

Alright Ill give those a shot. Wouldnt tps and iac throw ses codes though? Timing is good at right around 6°. Yeah those headers are such a pain. I have the right socket at home, but I figured the shop I go to would have it too. Go figure, they have every tool you could think of, except apparently a shorter plug socket lol

 

No, if the TPS or IAC are not set right it will not throw a code. Only if they stop working would you get a code.

 

How would you set reset them? Are there any articles on here? I always thought they were either good or bad n you just replace if need be

 

I noticed my car stopped popping when downshifting into a high rpm after I disconnected my smog pump I don't know if your emissions equipment would be causing misfire, but who knows, cars are strange sometimes.

 

Hmm thats an interesting thought. Most of my emissions stuff has been removed, maybe it has something to do with that. Ill try looking into that. Thanks

 

I'm planning on removing mine sometime soon...waiting for this rain to clear up(that's Oregon for ya), I've heard you're supposed to plug up EVERYTHING that was connected so you might check if some of your holes are open.

 

article on TPS

https://www.thirdgen.org/tpimod2

 

if your TPI is original you need to clean that bad boy up. if you feel behind the throttle blades $20 says your fingers encounter sticky black carbon. probably gunked up throttle blades too. i just did the IAC on my 87 tpi and ran a can of spray intake cleaner through it. made a world of difference. especially concerning idle quality.

 

alright Ill def look into that too. my tpi does have some buildup in it, doesn't seem too bad from the outside but who knows what it looks like farther in. I'll try that out tonight.

 

Follow the directions on the can, and don't use it while vehicle is in use!

 

https://www.thirdgen.org/tpimod2

This is the link to the tech article for IAC and TPS adjustment.

 

well a quick update. Finally caved and took the car to a mechanic today to get the header gasket that was leaking like crazy replaced. found out a couple of disappointing things while I was there though. pcv hose was kinked, so he replaced it, but while it was off he saw puffs of smoke while it was running from the pcv valve. pulled the dipstick and saw little puffs of smoke there too. What he told me that meant is that either the rings or pistons are worn out. for now though, its running a lil better with the pcv system working, and no exhaust pouring into the car is always a plus. guess its time to start saving for a rebuild though. >_<

 

well i got partway through the compression test, but i couldn't get past the headers on 2, 5, or 8. working on that today. so far so good though, all of em so far are in the range of 150-160. also think I found my rough idle. I noticed that there was a spark coming from where the coil wire attaches to the coil. gonna be replacing the coil and wire, and hopefully that's all it'll take to get her running better at least. still got smoke coming into the cabin though. I'm thinking it might be from the dipstick now. it's really loose and it might be splashing onto the exhaust or something stupid like that.

 

350 pistons aren't as much to replace as 305's, I'd say go to a junkyard and try to get some pistons.

 

I just kinda feel like if I'm taking the pistons out, I just might as well rebuild the rest of it anyway. not all that much more work to finish it up. plus, piston replacement, let alone a rebuild, is well beyond my ability right now. but then, I guess there's only one way to learn lol.
also, that spark I was seeing from the coil wire didn't fix anything, replaced the wire, and still no change. the car still wants to die at slow speeds when I let off the accel. coil and all other plug wires next. and for the record, I HATE HEADERS! they have caused me absolutely nothing but problems.no luck finishing compression test. tried 3 different testers and I couldn't get past the headers.

 

Cleaned intake, no change. Bottle of fuel injector cleaner, no change. The dipstick was loose, so I put on an o ring and some rtv to seal it. Unfortunately, theres still a ton of smoke coming out of dipstick tube and pouring into the car. Pcv valve is good so im not seeing any other options. Its major engine work for me

 

Bummer!

 

A common cause of exhasust gases getting into the crankcase in SBC motors, is the intake gaskets.

There's exhaust in the very center of the intake (feeds the EGR valve) and the bottom of that port is right next to the crankcase (lifter valley).

Replace the valve guide seals with "positive" type ones - NOT "umbrella" type, and don't even bother with the stock O-rings - and chang ethe intake gaskets.

Replace the oil pressure sending unit since those FREQUENTLY fail and usually do so by reading low and/or erratically, and see what happens to the gauge reading.

 

Also, pull the valve covers and check the rear oil drain holes to make sure they aren't plugged with old nasty oil.. Fixed a few smoking cars by cleaning the drains out. We thought the motors were shot but they werent at all.
Maybe you'll get lucky like we did but to be honest, the pufffing out the dipstick and pcv doesn't sound to good.

 

ok so I'm really seriously considering a valve job. It's a lot easier than rebuilding the whole thing. I'm worried it still won't fix the problem, but I don't have the time/money/skill right now to do a whole rebuild. before I do that, I'm gonna pull the damn headers off and get the rest of that compression test done. IF compression is good, does everyone agree that valve job is the best option? Or does it seem bad enough that I should just suck it up and do the whole rebuild. And thanks for all the help guys. I'm sure that the answer is here somewhere. I just gotta find it.

 

@sofakingdom, Im thinking the valve job, mostly because I get an occasional puff of blue smoke when I start the car and while I'm driving apparently there's some faint blue smoke too. not enough that I can see it in my mirrors, but my mom saw it while she was behind me.I want that gone too. figured if I have to do the intake, I'll just go a lil farther and take the heads off too. well, a lot farther lol, but I think it's worth it at this point.
@TTOP350, I'll check all that real soon. It'd be nice if it was that simple. thanks for the info.

 

Not to throw another answer out there for you to narrow down, but blue smoke on startup can be from bad rings.

 

Yep that's what I'm afraid of. I'm hoping that a compression check can at least count the rings out. Is that reasonable? or could rings still be bad even with good compression?

 

Valve job = take the heads off, take them to a machine shop, listen to them tell you all about how "we've got these 350 heads right here, all 350 heads are the same, [points to a pair of 70s smogger garbage or TBI heads or some such], just turn your [good heads] in as cores and take this pair [of trash] and be on down the road" and otherwise generally get ripped off; $300 or so later, maybe it's fixed, maybe it's not, your engine is downgraded by about 50 HP and somebody else now has your GOOD heads FOR FREE in exchange for some trash

Valve seals = spend $25 or so on valve cover gaskets & a set of "positive" (NOT umbrella and don't bother with the stock O-rings) and "rent" a valve spring compressor for free, and fix your wisp of smoke in a lazy Sat afternoon's piddling around

Which one sounds like the better deal?

It's EXTREMELY doubtful that the smoke has anything to do with rings. Procatically never does, unless the motor was either assembled incorrectly (recently) or SEVERELY abused. If neither of those things is true, don't worry about the rings. Your smoke is coming from something higher up.

And in any case, there are 3 rings on each piston. 2 of them seal against compression, the 3rd controls the oil. It's VERY easy for one to be bad and the others just fine.

Go ahead and do a compression test if you like; never hurts to know what it is; but don't expect it to tell you anything about oil burning.

In short, I would NOT do a "valve job" or a "rebuild" at this point, until the simple, eeeeeeeeezie, and cheeeeeeeeeep stuff has ALREADY been done and ruled out. I would not panic, despair, jump to conclusions, or otherwise act irrationally and stupidly either. I would take it one step at a time, do the simple stuff, and let it run its course.

 

@sofakingdom, right on. I appreciate it. Although I think this motor has been abused, I'll def try the easy stuff first. I'll be looking into getting valve seals here soon, and with any luck, that'll make a big difference. already have the valve cover gaskets. any advice on specific "positive" seals to use? part # or anything like that? And is there any kind of guide on here for doing this without taking off the heads? I know it can be done, just not quite sure how to do it.

 

never mind about the guide. good 'ol youtube. but some part numbers would still be much appreciated

 

Well I solved my problem... Took a remanned Jasper engine though. turned out that surging and dying was because of a hole in the piston. compression on the #5 cyl was at 60. So that's taken care of now lol. Not proud of having to take it to a shop, but I'm glad I did. Would have spent a good chunk of time and frustration trying other stuff that wouldn't have worked at all. Trying to trace down a couple other gremlins now. This one I'm a little confused about. The code 13 I've been having trouble with has been bugging me. I was thinking I would get a heated o2, but I wanted to test the wire to the sensor 1st. for some reason, when I probed the wire, it gave me 12.4 volts? If I understand it though, that wire is only supposed to have .3-.6 volts. Any thoughts there? I'm thinking bad ecm. anyone else ever seen this?

 

also wanna make sure I used the voltmeter right... maybe I just screwed it up? its possible lol. I've never used one before the last couple days. all I did was unplug the o2, stick red wire into o2 plug from engine harness, and ground to engine block. I did that right?

 

Yes you did that right. That wire comming from the O2 should have no voltage on the car harness side. <maybe 300 mV> The voltage from the o2 sensor should vary with the car RUNNING, anywhere from .1 to .9 normally. 1.1 MAX. A little FYI, a o2 sensor will generate its own voltage. Also, it has to be at correct operating temperature to work accurately. Normally a warmed up car will have a warmed up o2. (The reason they have heated O2's is so that it heats up faster, but that's another story.)

It is difficult to accurately test a o2 with a DVOM that does not graph. You can still test it to a point though. With the probe hooked up, disconnect the brake booster vac line and the o2 should flatline and stay at .2 or lower. Now hook that back up.

Next spray some carb cleaner or ether into the throttle body <A VERY SMALL AMOUNT AND BY SMALL I MEAN A 1/8 SECOND SPRAY>. The o2 should respond by going above .85 volts.

 

Alright thanks for the info. Any thoughts on why that wire would have 12v? Im wondering if ive got it plugged into the wrong wire. What color is the o2 sensor wire supposed to be? Ill check the sensor itself today, but its new so I dont expect it to be the problem. When I turn the car on(no start, jus on position) is the ses light supposed to flash once and then go steady? Or just stay steady on. My car does both. Ive seen it flash once, and just go steady as well.

 

hmmm, I looked into it a bit more, and saw that if the light doesn't flash when car is in on position, it means it's not reading from the PROM? is that true? I have no problem pulling codes... but with that on top of having crazy voltage to the o2 wire, I'm wondering if PROM, ECM, or both are bad?

 

02 wire is a single purple wire near the o2. If that wire has 12 volts there could be another wire shorting it out, or the pcm could have some kind of wicked internal fault. Also check pin E14 on the PCM to see if your also getting 12 volts there. That is the o2 wire at the pcm. Same purple one.

With the SES, its supposed to come on, go off, then come back on solid.
You have to wait 10 seconds between trys of cycling the key. If you do it fast it won't work.

 

Does your o2 have more than 1 wire going to it?

 

nope just the one wire. However, its not a purple wire? mine is attached to a yellow or brown wire?(dirty so not sure, but def not purple...) which side is the o2 sensor supposed to be on??? I just realized I had always heard it was driver side, but mine is on pass side... hmmm... well it seems I'm getting closer to the problem now. It effin continues to amaze me how much this car has been beaten and abused.
also, that makes sense with the ses.
Well, tomorrow I'll be trying to track down if my o2 is indeed in the wrong spot. seems very likely.

 

Uhhhhhh are you working with the fan switch? It's under the intake manifold near the starter area.

 

The o2 is on the drivers side manifold on the tpi's. It is in the exhaust manifold pointing foward just before the attachment point/collector for the y pipe.

 

Compression test? I though you already had a reman jasper in there cuz you found a dead piston? I re-read through the post but did i miss something?