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96 T-bird 4.6L -- rough idle with new intake manifold
Howdy folks,
This LX vehicle has 53,207 miles on it. It's garage-kept and aside from the
rough idle is in great shape throughout.
About 100 miles ago, the local Ford dealer replaced the old style intake
manifold on this car with the redesigned metal water channel version. The
original developed the classic cracked water channel right behind the
alternator. Back in '96, as soon as I got the recall notice on this part, I
took this vehicle to the dealer who sold it to me. That dealer informed me,
"oh no, this is not the problem part, no replacement is necessary."
Obviously, it WAS the problem part and a replacement WAS necessary! I
believe Ford even lost a class action suit regarding this very manifold, yet
the dealer informs me Ford will not reimburse me for the $1000 repair
because "the recall is only valid for 7 years". Well, I would have been
spared this nightmare had the dealer who sold the damn car to me replaced
the crummy plastic-channel manifold when I took it back to them!
I was just lucky enough to have the manifold crack and dump coolant right as
I was driving into my garage. Fortunately, this also meant I was able to
turn the engine off before the temp gauge got any higher than midrange --
prior to this incident, the indicator stayed at halfway between coldest and
midrange. Because of the very brief period of time the engine was allowed
to operate at above its usual temp and the fact that it never got past the
"normal" temp indication, I'm confident no engine damage occurred. The
dealer also made no mention of damage, if their opinion counts for anything
these days.
Ever since the $1000 dealer repair job, the car has been idling roughly
(stumbling sporadically) and hesitating upon acceleration. The lower the
RPM, the worse the stumbling. When sitting at stoplight in Drive, it nearly
dies. As you might surmise, operating the A/C compressor (a necessity in
south Texas right now) only drags the RPMs down and makes the prob that much
worse. No probs at city or highway speeds. No prob with acceleration or
power once it gets going (i.e., higher than around 900 RPM).
Here's what I've done so far:
1) verified manifold bolts are torqued within spec
2) cleaned injector connector contacts (prior experience on other cars
showed me this can be a recurring source of similar symptoms)
3) cleaned connector contacts for MAF, IAC, EVP, etc. etc. (yes, I had some
free time on my hands)
4) checked for vacuum leaks (hand vac pump)
5) checked EGR action with hand pump
6) checked fuel pressure regulator action with hand pump
7) verified MAF sensor is perfectly clean
8) systematically disconnected the various sensors to monitor effect (IAC
disconnect killed engine; ECT d/c caused fan to engage after about 3-4
seconds; MAF d/c had little to no effect, ditto for TPS, ACT and EVP.
I have no code scanner. I know, I KNOW, but I don't have one right now.
There has been no CEL/MIL indicator throughout this entire ordeal (except,
of course, when I momentarily disconnected the sensors; yes, I reset the EEC
to get rid of the CEL).
Air filter has 736 miles on it (clean as a whistle & lifting filter cover
made no difference in stumbling).
Oil and filter have 567 miles on them.
Fuel filter has 5,897 miles on it.
Tranny fluid (Mercon V) and filter have 6,268 miles on them.
I can't find a vac leak and I can't find anything else wrong with the thing.
I'm at a loss here.
I've no doubt the dealer will dodge and deny when confronted with the
prospect of correcting their recent $1000 error.. oops, I mean uhm "repair"
for free. What can I say? It wasn't doing this before they got their hands
on it and now it is. And no, it wasn't doing this the moment before I
turned the engine off that night of the manifold failure. They definitely
did _something_ wrong.
Unfortunately, this car is currently my only means of transportation and I'm
getting tired of hiring cabs to the dealer and back home. The dealer won't
provide a loaner car and they won't drive me home themselves, even though I
only live about 5 miles away! They were, in fact, SO uncooperative that
they flat out refused to stay after hours for even 5 minutes when I informed
them my cab had yet to pick me up, but that I _was_ going to be there _very_
soon. As it turned out, my cabbie rushed me out there just in the nick of
time to pick up the car. Prices keep going up and quality of service keeps
coming down. Is this supposed to make me want to buy another Ford? wow...
Anyway, any ideas on what components to look at next? If a relatively
inexpensive fix, I would gladly repair this myself to avoid future dealer
visits. I'm assuming another $589 (for a chunk of plastic and a bit of
aluminum?!?) in parts won't likely be required to correct this anomaly.
I'd also appreciate any useful ideas on how to: 1) get Ford to agree to
reimburse me for the repair and -- when you've stopped laughing -- 2) get
the dealer to correct their mistake at no charge to me. I hate the idea of
lawsuits, never been to court myself, but I suppose if worse comes to
worse...
Re: 96 T-bird 4.6L -- rough idle with new intake manifold
Check for water/coolant in the spark plug holes.
"Guy N. Aford" <guynaford@REMOVECAPSgmail.com> wrote in message
news:GQcXe.5234$Yu2.3207@trnddc02...
>I failed to mention the stumbling is slight when the engine is COLD, but
>gets severe when it reaches operating temp.
>
>
Re: 96 T-bird 4.6L -- rough idle with new intake manifold
Even better , pull all plugs out , check for carbon tracks on plugs AND
wires/coils.
Or just put new plugs in, they don't cost a fortune, make sure the
cables/coils are ok or you will end up with same problem
I've done a bunch of intakes and 70% of the time it had coolant in the holes
and just a trace of coolant can cause a misfire
"Shoe Salesman" <someone@microsoft.com> wrote in message
news:2afXe.8046$Gh.2261@tornado.socal.rr.com...
> Check for water/coolant in the spark plug holes.
>
>
>
> "Guy N. Aford" <guynaford@REMOVECAPSgmail.com> wrote in message
> news:GQcXe.5234$Yu2.3207@trnddc02...
> >I failed to mention the stumbling is slight when the engine is COLD, but
> >gets severe when it reaches operating temp.
> >
> >
>
>
>
Re: 96 T-bird 4.6L -- rough idle with new intake manifold
ford just settled their suite, and you will be getting a letter with a
voucher for reimbursement for the repair in the mail in the next few weeks.
I just got mine today for the 5 4.6 motored cars I have owned
"johanb" <ollieb1oREMOVE@THIScs.com> wrote in message
news:N8gXe.9$mI6.248@news.uswest.net...
> Even better , pull all plugs out , check for carbon tracks on plugs AND
> wires/coils.
>
> Or just put new plugs in, they don't cost a fortune, make sure the
> cables/coils are ok or you will end up with same problem
>
> I've done a bunch of intakes and 70% of the time it had coolant in the
holes
> and just a trace of coolant can cause a misfire
>
>
> "Shoe Salesman" <someone@microsoft.com> wrote in message
> news:2afXe.8046$Gh.2261@tornado.socal.rr.com...
> > Check for water/coolant in the spark plug holes.
> >
> >
> >
> > "Guy N. Aford" <guynaford@REMOVECAPSgmail.com> wrote in message
> > news:GQcXe.5234$Yu2.3207@trnddc02...
> > >I failed to mention the stumbling is slight when the engine is COLD,
but
> > >gets severe when it reaches operating temp.
> > >
> > >
> >
> >
> >
>
>
Re: 96 T-bird 4.6L -- rough idle with new intake manifold
"johanb" <ollieb1oREMOVE@THIScs.com> wrote in message
news:N8gXe.9$mI6.248@news.uswest.net...
> Even better , pull all plugs out , check for carbon tracks on plugs AND
> wires/coils.
>
> Or just put new plugs in, they don't cost a fortune, make sure the
> cables/coils are ok or you will end up with same problem
>
> I've done a bunch of intakes and 70% of the time it had coolant in the
> holes
> and just a trace of coolant can cause a misfire
>
>
> "Shoe Salesman" <someone@microsoft.com> wrote in message
> news:2afXe.8046$Gh.2261@tornado.socal.rr.com...
>> Check for water/coolant in the spark plug holes.
>>
Thanks guys.
I yanked the plug wires after reading your posts but the holes/plugs were
dry. Just to be sure of good contact, I sprayed the boots and plug
connectors with zero-residue contact cleaner and let the holes evaporate dry
before plugging the wires back on. The wires and coils are clean. The plug
wire connectors at the coils are clean -- well, the factory silicone grease
is still there. I could swap plugs, it's cheap as you say, but if fouled
plugs were the prob, I don't think they would have coincidentally caused
trouble immediately after the dealer repair, as they had no reason to yank
plugs or otherwise expose the tips.
I've read these engines are particularly sensitive to variations in wire
resistance. I suppose it's possible the dealer tech(s) may have damaged a
wire or three by leaning on them, dropping the old and/or new manifold on
them, etc. I did move the wires and boots around a tad with the engine
running and noticed no change. I'll check the wire resistance.
Been reading more on the subject and some owners have found that a dirty IAC
caused their rough idle. I peeked at the innards through the front hole.
It looked pretty clean, but I could yank it for a spray cleaning anyway. I
suppose the dealer tech(s) may have knocked some deposits loose inside the
IAC during the course of removing/remounting the throttle body. Other than
that, any more ideas as to cause?
Re: 96 T-bird 4.6L -- rough idle with new intake manifold
"tom" <tjctransport@optonline.net> wrote in message
news:7ejXe.7682$IC3.2076@fe12.lga...
> ford just settled their suite, and you will be getting a letter with a
> voucher for reimbursement for the repair in the mail in the next few
> weeks.
> I just got mine today for the 5 4.6 motored cars I have owned
I fear I am excluded in the covered vehicle class:
Re: 96 T-bird 4.6L -- rough idle with new intake manifold
Not a clue whether your problem is due to defective ignition wires or not,
but be advised that measuring their resistance is not likely to tell you
much. Unless you find something radically different than about 10Kohm/foot,
variations in resistance are not the problem. The typical failure is not the
bit of extra voltage drop across the wire, but a microscopic defect in the
insulation, causing arcing where it should not be and robbing the plug of
power. Some people advise to watch for arcing in the dark, but I never had
much luck with this method (not to mention the danger of messing around
rotating parts in the dark!!!) So basically you have a choice: pay to have
the ignition professionally tested ('scoped'), or take the plunge and
replace the wires. I would do the latter -- if your wires are the original
10 year old set, they are overdue for replacement anyway. And while at it, I
would replace the plugs too - for a good measure, if nothing else.
By the way, yes, removing and reinstalling old wires is very likely to make
a failure surface - at least in my experience.
Also, if I may, don't leave those contacts 'clean and dry' - do put some
silicone grease under the boot. Its purpose is to protect from moisture.
> I've read these engines are particularly sensitive to variations in wire
resistance. I suppose it's possible the dealer tech(s) may have damaged a
> wire or three by leaning on them, dropping the old and/or new manifold on
them, etc. I did move the wires and boots around a tad with the
> engine running and noticed no change. I'll check the wire resistance.
Re: 96 T-bird 4.6L -- rough idle with new intake manifold
On Sun, 18 Sep 2005 12:08:28 GMT, "Guy N. Aford"
<guynaford@REMOVECAPSgmail.com> wrote:
>Howdy folks,
>
>This LX vehicle has 53,207 miles on it. It's garage-kept and aside from the
>rough idle is in great shape throughout.
>
>About 100 miles ago, the local Ford dealer replaced the old style intake
>manifold on this car with the redesigned metal water channel version. The
>original developed the classic cracked water channel right behind the
>alternator. Back in '96, as soon as I got the recall notice on this part, I
>took this vehicle to the dealer who sold it to me. That dealer informed me,
>"oh no, this is not the problem part, no replacement is necessary."
>Obviously, it WAS the problem part and a replacement WAS necessary! I
>believe Ford even lost a class action suit regarding this very manifold, yet
>the dealer informs me Ford will not reimburse me for the $1000 repair
>because "the recall is only valid for 7 years". Well, I would have been
>spared this nightmare had the dealer who sold the damn car to me replaced
>the crummy plastic-channel manifold when I took it back to them!
>
>I was just lucky enough to have the manifold crack and dump coolant right as
>I was driving into my garage. Fortunately, this also meant I was able to
>turn the engine off before the temp gauge got any higher than midrange --
>prior to this incident, the indicator stayed at halfway between coldest and
>midrange. Because of the very brief period of time the engine was allowed
>to operate at above its usual temp and the fact that it never got past the
>"normal" temp indication, I'm confident no engine damage occurred. The
>dealer also made no mention of damage, if their opinion counts for anything
>these days.
>
>Ever since the $1000 dealer repair job, the car has been idling roughly
>(stumbling sporadically) and hesitating upon acceleration. The lower the
>RPM, the worse the stumbling. When sitting at stoplight in Drive, it nearly
>dies. As you might surmise, operating the A/C compressor (a necessity in
>south Texas right now) only drags the RPMs down and makes the prob that much
>worse. No probs at city or highway speeds. No prob with acceleration or
>power once it gets going (i.e., higher than around 900 RPM).
>
>Here's what I've done so far:
>
>1) verified manifold bolts are torqued within spec
>2) cleaned injector connector contacts (prior experience on other cars
>showed me this can be a recurring source of similar symptoms)
>3) cleaned connector contacts for MAF, IAC, EVP, etc. etc. (yes, I had some
>free time on my hands)
>4) checked for vacuum leaks (hand vac pump)
>5) checked EGR action with hand pump
>6) checked fuel pressure regulator action with hand pump
>7) verified MAF sensor is perfectly clean
>8) systematically disconnected the various sensors to monitor effect (IAC
>disconnect killed engine; ECT d/c caused fan to engage after about 3-4
>seconds; MAF d/c had little to no effect, ditto for TPS, ACT and EVP.
>
>I have no code scanner. I know, I KNOW, but I don't have one right now.
>
>There has been no CEL/MIL indicator throughout this entire ordeal (except,
>of course, when I momentarily disconnected the sensors; yes, I reset the EEC
>to get rid of the CEL).
>
>Air filter has 736 miles on it (clean as a whistle & lifting filter cover
>made no difference in stumbling).
>Oil and filter have 567 miles on them.
>Fuel filter has 5,897 miles on it.
>Tranny fluid (Mercon V) and filter have 6,268 miles on them.
>
>I can't find a vac leak and I can't find anything else wrong with the thing.
>I'm at a loss here.
>
>I've no doubt the dealer will dodge and deny when confronted with the
>prospect of correcting their recent $1000 error.. oops, I mean uhm "repair"
>for free. What can I say? It wasn't doing this before they got their hands
>on it and now it is. And no, it wasn't doing this the moment before I
>turned the engine off that night of the manifold failure. They definitely
>did _something_ wrong.
>
>Unfortunately, this car is currently my only means of transportation and I'm
>getting tired of hiring cabs to the dealer and back home. The dealer won't
>provide a loaner car and they won't drive me home themselves, even though I
>only live about 5 miles away! They were, in fact, SO uncooperative that
>they flat out refused to stay after hours for even 5 minutes when I informed
>them my cab had yet to pick me up, but that I _was_ going to be there _very_
>soon. As it turned out, my cabbie rushed me out there just in the nick of
>time to pick up the car. Prices keep going up and quality of service keeps
>coming down. Is this supposed to make me want to buy another Ford? wow...
>
>Anyway, any ideas on what components to look at next? If a relatively
>inexpensive fix, I would gladly repair this myself to avoid future dealer
>visits. I'm assuming another $589 (for a chunk of plastic and a bit of
>aluminum?!?) in parts won't likely be required to correct this anomaly.
>
>I'd also appreciate any useful ideas on how to: 1) get Ford to agree to
>reimburse me for the repair and -- when you've stopped laughing -- 2) get
>the dealer to correct their mistake at no charge to me. I hate the idea of
>lawsuits, never been to court myself, but I suppose if worse comes to
>worse...
>
>
>Thanks,
>Guy
>
Maybe I missed it but, I don't see where you may have
checked or cleaned the IAC. With the mileage you have and
the loss of coolant into the system, it is possible
(probable) that it needs a good soaking and cleaning. This
is also true since you mention the RPM dropping with the air
on which would indicate the IAC is not working properly. It
should be able to maintain a steadt idle RPM even it it is a
bit rough or stumbling on acceleration. A dirty/bad IAC
would explain the inconsistent idle, the roughness and the
stumble. Also, just looking at the MAF will not confirm
that it is clean. You need to use a residue free solvent to
clean it to make sure there is no oil film present.
Many auto parts stores will scan your ECM for fault codes.
In my area, Autozone does this. You should write down the
exact code and description from the scanner to post back
here. In the worst case, you may need to pay the dealer or
someone else a diagnostic fee to get the codes. A decent
shop will apply the diagnostic charge toward the repair if
you decide to have them complete the job.
There is a lot of knowledge here once you learn how to cull
the BS. They may be able to help you avoid the shotgun
system of auto repair. The shotgun is always loaded with
dollar bills from your wallet.
BTW, it sounds like you either have a bad relationship with
your dealer or they are incompetent - maybe both. You need
to find another source of service for your car. There are
quite a few competent independants out there.
Check with your friends and co-workers for references.
Linear Mode
