Hot stuff...

[cappy]

Hot stuff...still bucking

Hi all,

1st post here but I've trolled a bit on this topic and others....the amount of info here is crazy. Have a cooling question..or two.

My 1991 LX has had the FMS 3 core radiator and flex a lite 175 electric fan for about 6 years. Chasing a 'bucking' issue I have changed the spark plug wires (9mm FMS)and noticed that cylinder 3 and 4 boots were dry and brittle. Still having the bucking issue I check the new wires i had installed(Napa) and the boots at cyl 3 and 4 had a little blister and were turning to 'mush'...like they are getting cooked and I've only run it like six times since the change. Is it simply getting too hot in the engine compartment? (it also has BBK equal length headers.) The temp gauge reads fine when running. In the past year I've also done the starter, which is close to the header also, and starter relay(x2!) . The fan isn't always on and kicks on when it needs to. But, doesn't the stock fan ALWAYS run giving a constang flow of air? The way things are failing, seems the time when the electric fan is not running it is just cooking everything. Is my line of thought here off or what?

I intend to do a starter heat shield and spark plug wire boot shields and have to replace the wires themselves, AGAIN. But should I also consider ditching the electric fan? Or should I run the electric fan all the time? (The alternator is a 140 amp unit) The fan does have a dial to make it kick on at a lower temp...but I dialed it back just a hair since it seemed it was staying on too long after the motor was turned off....and like I said the temp gauge seems to be okay when driving. I would need to find out how to run it all the time if that is suggested.

And...I'm still chasing the bucking problem, thought it was solved, but will have to see how it runs after the new wires(any suggestions for wires)...it occured only twice in the six or so times I ran it so it is very intermittant. When the new wires are on I'll check in the dark for arcing(which I read about on this site!)

Well, I hope some of you read my whole story :violin:and have some thoughts to share. It's getting a little frustrating w/ this "mule", just when I thought it was finally running good!!!!

Thanks.

 

[HISSIN50]

In case I missed it, have the plugs been checked? If they're worn and the gap has eroded to a huge spec, the spark can start trying to find a new path of least resistance.

Your plan for the wire protection is good.

As far as the fan, your engine temps are ok?
If you need to dial the fan controller temp down but don't want it to run after the engine is off, simply wire the control side to be accessory controlled.

As for the wires melting, exhaust heat is much greater than cooling fan wash.

 

[Mustang5L5]

My BBK header do heat soak my entire engine bay. On a hot summer day, they really heat everything up. I haven't burned a plug wire or heat soaked a starter yet. I have the unequals.

Have you considered header wrap? Will make a difference and the BBk will rust up soon anyway, so they won't look that bad wrapped.

 

[cappy]

Thanks guys,

Hissin, Yes the plugs were replaced about 4 months ago when I started chasing the buck problem. If the new wires(w/ proective heat sleeves) don't solve the buck I can add checking for an excessive plug gap to the list of possibilities. Then next would be grounds, then on to searching more threads!! The temp seems okay using the stock temp gauge btw.

5L5, The header wrap would be a challenge to get around them pipes. Maybe if they were off the car!

Hopefully I'll get the parts all ordered today.

 

[cappy]

update....Koeo video

Wow, can't believe it's taken me a month to get back to this. But I have rec'd parts in the mail and installed new wires, protective wire boots, wire separators and new plugs. Even though the plugs that were on there were new I swapped in copper ones vrs the platinum after reading that platinum plugs may cause issues and to also check the gap(thanks Hissin). I did this since I am still having the bucking issue. I was hopeful that the plugs were the issue as the gap on a couple of them was large at around .07. The bucking seems to happen after it warms up and is very intermitant. All the grounds HAVE NOT been checked as I'm still trying to find out WHERE all the grounds are. If you have a link to a post about that let me know. By the way I also checked the enginge compartment in the dark, sprayed a water mist and did not find any arcing. But.... I have done the KOEO, KOER and Balance test using the MIL malfunction indicator lamp. Pretty neat stuff, I've always appreciated mechanics but really can't believe how intricate a car actually is. Anyway, the balance test came out 9's, which is good and the KOER test I believe gave me 11, 11. But the KOEO test was a little hard for me to read and hope someone can post the codes interpret them for me...here is the video: YouTube - ‪IMAG0042‬‏

Thanks so much and hopefully the code isn't a 36,000 code which means buy a new 5.0!!! I just want to fix her up and get her reliable again.

 

[Mustang5L5]

But the KOEO test was a little hard for me to read and hope someone can post the codes interpret them for me...here is the video: YouTube - ‪IMAG0042‬‏

Code 14
Code 96

http://www.stangnet.com/mustang-forums/751638-error-code-14-what-does-mean.html

http://www.stangnet.com/mustang-forums/538021-anyone-know-how-fix-code-96-has-do-fuel-pump.html

 

[Gearbanger 101]

In my experience....most "bucking issues" under light or no acceleration associated with the early 5.0L's were a result of excessive engine timing.

Just because you're not hearing a "ping" under load, doesn't mean that running that much timing is always a good thing. Try backing it off to the stock 10-degree's and see if it goes away. If it does, experiment in 1-degree increments until it comes back and back it off half a degree or so until it goes away again.

The stock mechanical fan does not in fact run all of the time. They're clutch based so when the element inside heats up, they clutch engages and kicks in. When it's cooled down enough again, the clutch disengages. They will always spin a little while the engine is running, but unless under hood temps increase enough to engage the clutch, it shouldn't be running all of the time. If it is, it's a sign of a bad clutch.

 

[l2ol33rt]

I had similar problems with bucking on my '91 and after changing plugs, ignition wires, etc. it ended up that my distributor was bad. Maybe its worth swapping in a know working distributor and taking the car for a spin.

 

[Mustang5L5]

Code 14 dpes point to a distributor issue. Might want to investigate that.

I think its a timing issue, nut could be the result of a faulty PIP in the dizzy

 

[cappy]

Thanks for the reading the MIL for me 5L5. Out of all the threads I read I did not come accross timing as being a culprit for cutting out or bucking. Thanks gearbanger and 5L5 for mentioning that. If it stops raining I'll check that out today as I havn't done it in years since I bumped it when I started reading magezines hoping to do a 12 sec quauter just by bumping the timing...lol. I think its at 13 or 14. Will make sure its at 10 since its simple and free then move on. The bucking does seem to happen at low speeds more more oftern than not, like when coming to a stop.

I hope its not the dizzy l20l...something I haven't worked on before, is that a tough swap? does the whole thing have to be changed or just the PIP? Is the pip at the bottom?

How about the 96 code? Seems like it could be pointing to several things...pump, relay, wiring.

 

[l2ol33rt]

I hope its not the dizzy l20l...something I haven't worked on before, is that a tough swap? does the whole thing have to be changed or just the PIP? Is the pip at the bottom?

It was easy to swap, I had a spar in my garage so I just swapped the entire distributor. If your going to do the PIP I came across a thread that was pretty thorough:Rebuild Install PIP, Distributor Stator, Pick-up, pickup

 

[cappy]

Well, managed to bring the timing back to stock, I was hoping it was really off, but it was at 14, so I brought it back down to 10. First test ride was fine but the second ride was my own little rodeo as it bucked 3-5 times. At least it didn't leave me stranded!!

Thanks for the link l2ol...I think that is my next project. There is a used dizzy on ebay, I think it also has the tfi module and cap, for a lot less than new Ford. There is also this unit http://cgi.ebay.com/ebaymotors/86-9...ptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories from Richporter? The description seems good and made in "north america". Has anyone used one of these? So, used Ford or new Richporter?

BTW thanks gearbanger for the info on the fan.

 

[cappy]

Update: Well I have the distibutor off and want to replace the TFI module when I get the part tomorrow. I'll order the distributor if that doesn't fix it. Is there any part on the distributor or TFI that is supposed to look "bad"? Under the tfi cover the electronic parts under the 'gel' look new! I lucked out since my socket set was skinny enough to get the tfi off. Distributor gear looks good, no filings or anything, but I really don't know what to look for either.

Thanks folks.

 

[cappy]

Well, the new distributor and tfi module didn't fix the issue either...but a new coil made it a lot better. It does not stall now or buck...but now it just seems low on power, definitely does not buck but will hesitate, or I might even use the word skip. A lot more 'drivable' now but still not totally running right yet.......any advice would be appreciated. Thanks.

 

[l2ol33rt]

hmm my next guess would be the fuel system. Maybe its the fuel filter, fuel pump or regulator? Im not to sure on that though.

 

[VibrantRedGT]

Have you checked the free stuff first like a vacuum leak? You've changed a lot of parts and might have missed this in your text. Every vacuum hose on the 92 was brittle or torn. Replacing every hose right now.

 

[cappy]

Maybe its the fuel filter, fuel pump or regulator?

Well, could be, it had a 96 code in the past. I just cleared codes, swapped back to the old distributor and TFI module. Checked timing. Went for a couple of rides and it still has the 'hesitation' problem and the new codes are 14 and 18....no 96, which is fuel related.

Could it still be fuel related even though 96 does not appear in the KOEO test?

The hesitation now only happens when I am driving faster than your supposed to on the street. There is a half mile streatch of road near my house with good visibility that goes up hill, so I can give it a bit of thottle there. So under a pretty heavy load it'll 'hesitate' or 'bog' or 'skip'...not be up to full power...but very slightly...can barely notice it sometimes. Idle and driveablity seem good.

Have you checked the free stuff first like a vacuum leak? .

Good luck w/ changing the vacuum lines. Think I mentioned it in the thread, but I did spray water mist around the engine while it was running. Is that a sufficient test for vacuum? Could vacuum cause the hesitation now? Man, there are so many different things it could be! But its not really bad right now so I'm lucky I can still drive it...hope it doesn't get worse.

Thanks so far!! Any thoughts....

 

[cappy]

One Year 5 months. Man, thought I was going to take it out to the pasture and put it away. But, I think its running well now. As far as the time lapse...., I had the car parked at my folks house since I was rebuilding the garage. I had it jacked up, replaced the slab, added 10x10 and reframed the joists. The garage isn't totally done, but its weather tight and keeping the Mustang dry!

Anyway, just drove the car back to my house 3 weeks ago and of course it was still missing or bogging when under load. It started and idled fine even after sitting so long, but it just lost power when giving it a bit of gas. I cleaned out the IAC and adjusted the TPS at the same time so don't know which one fixed it. I think it was the TPS since it was at 0.74 at idle. Correct me if I'm wrong, but the TPS adjustment effects how it runs and not just idle, right?

 

[HISSIN50]

One Year 5 months. Man, thought I was going to take it out to the pasture and put it away. But, I think its running well now. As far as the time lapse...., I had the car parked at my folks house since I was rebuilding the garage. I had it jacked up, replaced the slab, added 10x10 and reframed the joists. The garage isn't totally done, but its weather tight and keeping the Mustang dry!

Anyway, just drove the car back to my house 3 weeks ago and of course it was still missing or bogging when under load. It started and idled fine even after sitting so long, but it just lost power when giving it a bit of gas. I cleaned out the IAC and adjusted the TPS at the same time so don't know which one fixed it. I think it was the TPS since it was at 0.74 at idle. Correct me if I'm wrong, but the TPS adjustment effects how it runs and not just idle, right?

The EEC should have accommodated it (it baselines the TPS at the start of each drive cycle. It can usually handle a reading down to around 0.5V). If it can't handle it, it throws a TPS code.

Garage pics?

 

[cappy]

Well since you ask here are some garage pics. Don't have any in its current state. I was unemployed while I did most of the work...even now I am part time btw. I hired out for the slab, new shingles and someone helped me with the jacking. I did the framing, sheathing, trim, vinal electrical and general grunt work.

So you think even at 0.74 the tps could have been okay? I did read about the TPS 'baseline' at startup. But my last drive was pretty smooth. ALL the missing/bogging, which wasn't VERY severe...was 99.9% gone. I think I'll check timing again, check for codes and cant wait to drive it later.