Weird smell

Patriotu

New Member
Nov 6, 2016
26
1
3
No moods on the car. Just some exterior ones.

A few months ago car start to “smell” when i “jump” on the pedal. On 4,5-5 RPM s start to smell like something i never smell before on a car. Its not clutch or antifreeze. Thats i know for sure. Smells inside and outside.

Back than, the smell seems to develop just on high rpms. Now its there all the time after car warm up. And its not a pleasant smell. And also very persistent. Persist in garage after days.

Car works fine, no other “turbulences”. Just an increase of MPG in town. About 13 and i had around 15.

Highway its the same, 20 mpg.

The car sits in garage for winter time.

Car has 25000 miles , v8, manual, 2008. Never had big issues with it. Shaker 1000 went bad and i replaced it. 2 years ago i upgrade with fr500 exhaust and wheels.

I live in Romania, Europe and a diagnose for my car its not possible. I did it with my BLUE DRIVER but went fine. No bad codes.

Please share some thoughts. Thanks.
 
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Hi,
Welcome! This still has Catalytic Converters- correct? During hard driving, exhaust temperatures spike quick & they may produce a “rotten egg” smell under some circumstances, especially if it’s low mileage & not been driven too much & it’s driven hard, rather than casually over long distances. Doesn’t typically linger around afterwards, however.
New Cat’s installed with your new exhaust?
-If you’re NOT running Cat’s- another smell may develop, like fuel- but not a pleasant one. In fact, it’s so irritating many re-install their Cat’s.
May have wiring or something else on the Car contacting your Exhaust & melting when the temp rises (even a plastic bag from the road). take a look.
Take a look under your hood, replace your air filter element if it’s in need, look for any wires or vacuum lines very close to, or contacting the exhaust manifolds & possibly melting.
Some fuels may cause an odor that permeates the Car, has anything changed around the time you started noticing this, new Oil, any Service?
Don’t worry about it, will keep on helping you here until it’s located.
Can you say whether it smells most like plastic, rubber, brake or clutch, or Petroleum- based on odor?
I’ve 3 2008’s, one Mustang GT with 77K one GT500 with 18K, another 08’ GT500 caught in a flood just bought @ auction.
Good luck!
-John
 
-"This still has Catalytic Converters- correct? " - correct

-"low mileage & not been driven too much & it’s driven hard" - that s correct, but my mustang always had the same routine and no smell before.

- no new cats installed but i just bought this https://www.americanmuscle.com/bbk-catted-xpipe-0510gt.html . I didnt install it yet because i don t want to have lights in dashboard after that. What do you think ?

-"May have wiring or something else on the Car contacting your Exhaust & melting " - NO, i double checked everything. The only difference i have noticed ,but i don t think they are related, the AC was like ice all the time. Now its more like half than before. And we checked the freon . All good. No leaks.Not even 10g.
 
Hi,
Nice speaking with you, I can walk out & look at my 2008 & verify things, lol!
Regarding the A/C, actually, I believe quite the contrary. Your A/C may explain the entire problem you’re experiencing...
With your A/C symptoms, you may have a faulty/slipping or dragging A/C Clutch or a Compressor issue, this slippage may cause performance loss of the engine and A/C System, as well as a high temperature odor, burnt smell, that “lingers”, and more likely to be excessive at higher RPM’s.
1) Inspect the Clutch for excess media around it & surrounding areas.
1A) After you take it for a drive & start smelling that odor, pull over, pop your hood & see it that’s where the odor Emanates from, it may be very hot!
2) Pull the Belt and spin the A/C Compressor by hand, see if there’s excessive resistance.
3) Inspect the Belt for cracking, if you ever had a belt squeal, replace the Belt with a ‘Gatorback’, they grab well, long service life.
4) Take a sniff around the A/C clutch, is this consistent with the odor experienced?
5) Take the opportunity to check all your other accessories, verifying all spin with little resistance and no noise or bearing issues you can feel by applying downward force while rotating slowly, it’ll transmit a rumble you’ll feel.
The X-Pipe you chose May cause a CEL, but only because the warm up time will likely be longer for the 02 sensor. There’s a preset parameter for the 02 sensor in the CPU’s program to be at a certain temp within a timeframe. If it takes longer, the CPU throws a Code.
That being said, I’d look at an SCTX4 Bama Tuner with BAMA’s “free Tunes for life”. As long as you own the Car, they will provide new Tunes via E-mail or directly to your Home WIFI, the Tuner connects to the WIFI & downloads the Tunes directly into the Tuner.
They can offset the CEL being thrown by the new X-Pipe, and with a Combo of Cool Air Intake & their Tune, gain you 35RWHP & 40GT/Lbs of Torque- all while increasing fuel economy. Likely more with your Exhaust.
My GT has an Airaid Intake & the above, the Tune’s throttle response improvement, alone made the OE Tune feel like I was driving a 6,000lb Car.
BAMA’s process is streamlined, tell them what parts you have, they have your Tune within 48Hr’s. Any future Mod you make, you’re covered.
Keep us posted!!
Good luck!
-John
 
Hi,
Nice speaking with you, I can walk out & look at my 2008 & verify things, lol!
Regarding the A/C, actually, I believe quite the contrary. Your A/C may explain the entire problem you’re experiencing...
With your A/C symptoms, you may have a faulty/slipping or dragging A/C Clutch or a Compressor issue, this slippage may cause performance loss of the engine and A/C System, as well as a high temperature odor, burnt smell, that “lingers”, and more likely to be excessive at higher RPM’s.
1) Inspect the Clutch for excess media around it & surrounding areas.
1A) After you take it for a drive & start smelling that odor, pull over, pop your hood & see it that’s where the odor Emanates from, it may be very hot!
2) Pull the Belt and spin the A/C Compressor by hand, see if there’s excessive resistance.
3) Inspect the Belt for cracking, if you ever had a belt squeal, replace the Belt with a ‘Gatorback’, they grab well, long service life.
4) Take a sniff around the A/C clutch, is this consistent with the odor experienced?
5) Take the opportunity to check all your other accessories, verifying all spin with little resistance and no noise or bearing issues you can feel by applying downward force while rotating slowly, it’ll transmit a rumble you’ll feel.
The X-Pipe you chose May cause a CEL, but only because the warm up time will likely be longer for the 02 sensor. There’s a preset parameter for the 02 sensor in the CPU’s program to be at a certain temp within a timeframe. If it takes longer, the CPU throws a Code.
That being said, I’d look at an SCTX4 Bama Tuner with BAMA’s “free Tunes for life”. As long as you own the Car, they will provide new Tunes via E-mail or directly to your Home WIFI, the Tuner connects to the WIFI & downloads the Tunes directly into the Tuner.
They can offset the CEL being thrown by the new X-Pipe, and with a Combo of Cool Air Intake & their Tune, gain you 35RWHP & 40GT/Lbs of Torque- all while increasing fuel economy. Likely more with your Exhaust.
My GT has an Airaid Intake & the above, the Tune’s throttle response improvement, alone made the OE Tune feel like I was driving a 6,000lb Car.
BAMA’s process is streamlined, tell them what parts you have, they have your Tune within 48Hr’s. Any future Mod you make, you’re covered.
Keep us posted!!
Good luck!
-John

So, i did check the PCV, all good, i did an ecu test for the engine and no code. The o2 good, the air-fuel mix good. I did check the exhaust front to rear. I checked the AC components, seems to be all right. The only thing i ve noticed was a very thin oil layer on oil filter and also on ac compressor, near the oil filter. But i dont know where its coming from. May be ac oil or engine oil. I dont think it can cause any kind of smell or problem it all.

I upgrade the gas and turn off the AC. And no smell. I ran the car on high rpm s like i always do and ALL GOOD. The bad smell is gone!!

Now i have to figure wich is who :)

I also upgraded with Hurst comp shifter and its a great improvment over stock.

The look is great and shiffting thru gears its more fun. But i have a rattle between 2.8 and 3,5 rpms. Have any ideeas how to get rid of it ?

Thanks, Dan.
 
Hi,
Excellent! Wanted to ask more about the Fuels over there, and if you stick to one station or use whatever, whenever. Some Companies get fuel that’s not well refined, what octanes do they offer, it contain 10% Ethanol?
Running a LUCAS fuel stabilizer is not a bad idea.
Heard a rumor of 95 Octane potentially being offered in the US to reduce emissions, (87-91-93 Octanes, here, now. Some spots in US, offer a max of only 91). Thought it was some part of Europe that offered the higher 95 Octane at the Pump(?)
I’d Run Higher Octanes with your Mustang, 91 Min. My Pony likes to Drink B.P., 93, it’s fairly common that some Cars prefer specific fuel sources.
You’d be AMAZED what a good Airaid filter & BAMA Tune would do with your Car’s performance, I create tunes using BAMA’s “Derive III” Software, & HPTuners for OBD-2 Vehicles, was surprisingly pretty impressed how good the BAMA Tunes are. They Dynotune the Cars they offer Tunes for, so good Tunes aren’t so unusual..
A Smell, that hangs onto the Car Days after from Fuel is not something I’m aware of, unless Cat’s get way too hot, or if Muffler packing melts..
A burnt Oil smell WILL linger, smells awful, source especially around an A/C Clutch that engages, and the CPU automatically disengages your A/C Clutch at Wide Open Throttle to reduce parasitic losses. Oil may also cause slippage during normal Compressor Loads.
This anomaly (rattle) you described occurred after the Shifter was installed, or was there, previous? It’s something felt through the shifter, itself, or is it more of a vibration you also feel in the Steering wheel? Can you replicate when revving the motor when the Car’s in neutral, or only when the Cars in motion at a specific RPM,?
Try running it in a different gear to see if it correlates with speed, vs only 2,800-3,500 using your normal shifting patterns..
If Only a Rattle, not a vibration that’s present whether driving or at a standstill revving at that RPM range, it may simply be caused by a heat shield contacting the exhaust, exhaust contacting the Car, Exhaust mount loose somewhere. Harmonics just right at that RPM to cause the noise.
4.6’s are internally balanced Motors, but if it’s not when the Car’s speed happens to hit the spot where the rattle is & also a slight vibration, like a Tire out of balance (the Sticky weights added to the Rims are notorious for falling off), then we can look at other causes.
Locate the Oil leaks, everything should be addressed prior to looking further than a simple exhaust contact to Chassis. The Filter housings May crack, more than likely something more simple. No “milky” substance within your Oil-correct?
Good luck!
-John
 
Hi,
Excellent! Wanted to ask more about the Fuels over there, and if you stick to one station or use whatever, whenever. Some Companies get fuel that’s not well refined, what octanes do they offer, it contain 10% Ethanol?
Running a LUCAS fuel stabilizer is not a bad idea.
Heard a rumor of 95 Octane potentially being offered in the US to reduce emissions, (87-91-93 Octanes, here, now. Some spots in US, offer a max of only 91). Thought it was some part of Europe that offered the higher 95 Octane at the Pump(?)
I’d Run Higher Octanes with your Mustang, 91 Min. My Pony likes to Drink B.P., 93, it’s fairly common that some Cars prefer specific fuel sources.
You’d be AMAZED what a good Airaid filter & BAMA Tune would do with your Car’s performance, I create tunes using BAMA’s “Derive III” Software, & HPTuners for OBD-2 Vehicles, was surprisingly pretty impressed how good the BAMA Tunes are. They Dynotune the Cars they offer Tunes for, so good Tunes aren’t so unusual..
A Smell, that hangs onto the Car Days after from Fuel is not something I’m aware of, unless Cat’s get way too hot, or if Muffler packing melts..
A burnt Oil smell WILL linger, smells awful, source especially around an A/C Clutch that engages, and the CPU automatically disengages your A/C Clutch at Wide Open Throttle to reduce parasitic losses. Oil may also cause slippage during normal Compressor Loads.
This anomaly (rattle) you described occurred after the Shifter was installed, or was there, previous? It’s something felt through the shifter, itself, or is it more of a vibration you also feel in the Steering wheel? Can you replicate when revving the motor when the Car’s in neutral, or only when the Cars in motion at a specific RPM,?
Try running it in a different gear to see if it correlates with speed, vs only 2,800-3,500 using your normal shifting patterns..
If Only a Rattle, not a vibration that’s present whether driving or at a standstill revving at that RPM range, it may simply be caused by a heat shield contacting the exhaust, exhaust contacting the Car, Exhaust mount loose somewhere. Harmonics just right at that RPM to cause the noise.
4.6’s are internally balanced Motors, but if it’s not when the Car’s speed happens to hit the spot where the rattle is & also a slight vibration, like a Tire out of balance (the Sticky weights added to the Rims are notorious for falling off), then we can look at other causes.
Locate the Oil leaks, everything should be addressed prior to looking further than a simple exhaust contact to Chassis. The Filter housings May crack, more than likely something more simple. No “milky” substance within your Oil-correct?
Good luck!
-John

I always use the same gas station. Never random. Until last year i filled up with the best gas(which is 98 RON or 100 RON), but after i did some forum readings i came to conclusion that its best to use the gas for what car its made for. So, i came down to 95 RON, which is 91 octane in usa.(approx).And yes, gas here contain up to 10% Ethanol.
I run STA BIL https://motoarebarci.ro/stabilizator-combustibil.html , but just for winter time.
"I’d Run Higher Octanes with your Mustang" - that's definitely gonna happen from now on. Maybe that s why start to smell, when i lowered the octane.I thought doing this its not safe for engine, the same like using lower octane that it needs.
I ve always wanted a filter and tune for my car and actually that was my option also, Airaid filter & BAMA Tune, but i had to pass it because 1 its way to much dust here for that kind of air filter and 2, i cant use a tune because gas here its not the same gas like you have there, and also different blend. And i m sure its gonna be trouble. And 3 , the mechanic told me so.
'' unless Cat’s get way too hot, or if Muffler packing melts'' - can we check it ?
" This anomaly (rattle) you described occurred after the Shifter was installed, or was there, previous?" - No, it wasn t there before. Everything was nice and smooth. Now, its more fun, its a bit notchy which i like it, its shorter than before in changing gears, but i have this noise , which its not very bad, but its there.
" It’s something felt through the shifter, itself, or is it more of a vibration you also feel in the Steering wheel? " - YES and NO. The steering wheel is concrete,no problem there. It s a vibration which it feels just in shifter when Car is in motion at a specific RPM like 2,8-3,5. If i have the hand on the shifter all the time when shifting and after , i dont hear anything , just feel a vibration in my hand..
"No “milky” substance within your Oil-correct?" - Correct.
Thank you, John. I ll look forward to the next steps described in your post and keepin touch.
dan
 
Last edited:
Hi Dan, Was typing to another & I saw your response. Would like you to try something, temporarily put the shifter back in, you may just be feeling the normal trans operation,
The OE Shifter handle was padded-right? New ones Billet Steel?
May just be a combo you couldn’t feel as much, and.also possibility that-its adjusted slightly too much or little. You’d mentioned it was adjustable. You may be engaging in too far, meshing teeth that were never tengaged so deeply, or may be in slightly be slightly on the shy side of engagement , both which are dangerous & can create media in your Oil, stress cracks and/or bearing failure.
Want to caution you of this, as I’ve seen 800Mile old Transmissions fail for this very reason..you want 0.015-0.025 In between major gear diameter & minor..
I was ironically going to
Get you started with the most effective oils made for these Transmissions, Motors, and tear ends, including Compressor oil.

going to recommend a Transmission Fluid that will extend your gears & syncro’s, Bearings by many miles Royal Syncromax Purple, stuff is liquid gold, not too expensive & works great. Run it in all my Mustangs, Z-28’s, Corvette’s, and recommend to my Customers.
. No worries, I’ll be available for a Pony- obsessed member in need! Lol!
-John
 
Dan, on the Tuning issue, not the most important now, but they offer 87 Octane to 93 Octane, I’d verified & it will be OK to try a 91 Octane 1st, there are many other octanes they make tunes for, not generally over 93, and the Airaid and others make a decent seal when the Hood is closed, the Filter being a reusable type that uses a lubricating oil on it to catch the water or dust, whether condition it is.
A guy from South Africa actually bought one of my Tunes, a chipset with Bluetooth I designed and made myself, for hit Range Rover, and his 14’ 5.0. No issues with dust, which half the roads he travels are laden with, told him to monitor his Filter more often is all. Gained him +6MPG, and 20Ft/Lbs, 32Hp at the wheels running 91.
Something to think about...
Ok, will chat a bit later- k?
Best- John