[Ninety3Coupe]

Hello guys. Just signed up since I have heard great things about you guys over here. I have a head scratcher and my previous forum is more geared toward newer Mustangs and didn't have the experience you folks do - I hope you guys can help. This could be multiple issues, or one issue causing a couple symptoms.

I bought my car very, very stock (true 92,xxx miles - hasn't rolled over). I have done a lot lately and developed an issue. I will try to keep this shorter than a novel yet give all the details.

I installed a BBK Catted H Pipe and it rattled, but I kept it on and it drove fine (this becomes important later). Everything was great, but it rattled. Car drove great.

I installed the Edelbrock Intake Manifold and everything else intake wise was stock. The car ran great!

I got the AccuFab 70mm TB with the BBK CAI and I developed a stumbling issue. It would start to go, fall on it's face, then GLH about 3500rpm.

I then started to notice the smell of varnished gas (bad gas) and while cruising at near idle looking for a business (maybe 10 minutes) it refused to start. After 20 minutes it fired right up. Didn't happen again for a month.

I then ditched the BBK Catted H Pipe back for the stock H Pipe (almost to the reason I mention it).

The other folks suggested I get a fuel pressure regulator and bump the pressure to fix the stumble, so I did. It did help a tiny bit, but I saw that the fuel pressure wouldn't hold when the car was off (gauge went to zero immediately). So I bought a new Walbro 255lph pump and dropped the tank and put it in last week. The tank is clean and clear and the gas smells like the new gas it actually is. The bad gas / varnish smell is not bad gas in the tank - the gas is perfect.

I put it back together and the smell of bad gas (varnish) is still there when the car warms up and I am idling in traffic. Now it is officially a VERY bad / powerful smell, worse than before for sure.

I have heard that O2 sensors can maybe cause some of this and since the H Pipe has been pulled a couple times the mechanic could have damaged or contaminated them. Thoughts? I am waiting for the new ones to arrive in the mail now and will swap them this weekend.

The bump in fuel pressure since the new pump seems to really have helped - if not fixed the stumbling but I don't know. I hesitate to hammer the throttle until I know what is really going on, but it seems better. I am just afraid I am not fixing the real issue and masking it. I set the fuel pressure to 52psi with the vacuum disconnected - which seems really high. The injectors are stock 19# with new (oiled) o-rings when I did the intake manifold.

I have checked the Charcoal Canister and the hoses, they all seem fine - But I think the smell comes from near the Canister. The vacuum line going to under the upper intake is new and the others look good.

Sorry again for the long post guys, I just want all the facts here to "help you help me". I appreciate any and all help and thanks for having me here! If you need any more input please ask and I will do my best!

[ryanw]

Id put your fuel pressure back to 39 psi with vacuum line off.

I believe its normal for the fuel pressure to fall when car is turned off.

Did you set the tps sensor to the correct volt when you installed in on the new tb ?

When you installed the new intake, did you have to pull the distributor out, and if so, did you put is back in the correct position ?

And when you set the timming, did you remeber to pull the spout conector? Setting the timming to 10 btdc.

Check your radiator fluid for oil and check your oil for water, its possible that the gasket sliped when you installed the intake .

[Ninety3Coupe]

Thanks Ryan, I have been reading your posts. You know your stuff.

I set the TPS and I have replaced it since then with a new one (and reset it again). It's around .975ish now...

I did pull the dizzy when I did the manifold, but again, it ran great for weeks and weeks after I did so. It is only maybe a month later when I did the TB and CAI that the stumbling started. I never noticed the varnished gas smell during that time either. All bad things occurred long after the manifold went in.

The spout connector did in fact get pulled (and put back) and the timing is at 12 degrees.

The coolant is clean, as is the oil. No cross contamination.

Great questions, keep 'em coming. I wanted to detail everything, but not overload with too much info. Thanks again for the help!

[ryanw]

Originally Posted by Ninety3Coupe Thanks Ryan, I have been reading your posts. You know your stuff

Ha ha thanks, but not really, i just play it off, im like a parrot, i just repeat whatever i hear...lol

[brandon444]

did you plug your mass air flow sensor back in when you did the cold air intake? did you put one back on?

i forgot to plug mine back in one time and it ran like crap, also try cleaning it

[ryanw]

Check your codes , but like i said id put your fuel pressure back to stock. After checking codes id reset the computer then after its been running for a while with normal fuel pressure id check the codes again.


Fuel Injector and Fuel Pump Calculator
KOEO, KOER, CMM and balance test codes 2 digit and 3 digit

[Ninety3Coupe]

It turns out Ryan is probably the problem child in the group. Good to know that early on! lol I'm just playing dude...

Brandon, you're up next. Yes sir, it is plugged in, and has been checked and rechecked more times than I can count (without taking my shoes off anyway). I have also cleaned it as well thinking the CAI had too much oil from the factory and got the MAF oily. No luck, that wasn't the issue.

And while we are on this topic, I will say I have checked all the vacuum lines, nothing. The intake tract has been checked a million times for leaks at the clamps...nothing there either.

Other new parts (but were all installed BEFORE the problems began) are wires, cap, rotor, plugs. Those can be eliminated from the discussion I think.

I will try lowering the pressure as suggested, but I know it is gonna run really poorly again.

The real tragedy here is I have a dyno day on the 11th that the ricers at work have invited me to. Can you imagine the horror if I can't beat a Honda on the rollers? Seriously guys, this makes it serious! lol

[Ninety3Coupe]

Ah crap. Sorry Ryan, just saw your latest post. I checked the codes too. I have code 67 and 11. 67 was because I'm a doofus and didn't take it out of gear while doing the test and 11 means everything is just dandy.

And then...?

[BassMaster5000]

Was the smell of bad gas worse/stronger when you turned the fuel pressure up?
Do you still have the O2 sensors on the car? If so, try unplugging them and try to observe any changes.
Do you have access to an OBD-I reader?
+1 to turning your fuel pressure back down to see if the studder still exists after the fuel pump change.

[BassMaster5000]

Disregard the code reader, just saw the other post.

[Ninety3Coupe]

If I am not crazy (which is still up for debate) the smell did get a lot worse when I bumped the pressure with the new pump.

On my first drive after the pump the pressure was set to about 45ish psi. It still stumbled. I drove it for 15 miles and parked it and let it cool down. Someone told me to bump it to 50 so (being a man) bumped it to 52 (more is always better right? No? Oh hell) and it ran better.

But that is just too high, and it is not the right fix for the issue, I am sure. Something else is going on here...

I do have the O2 sensors (original I believe) plugged in. I didn't know I could unplug them and then still start the car and drive it (for testing purposes only I am sure).

I will lower the pressure to 40psi, disconnect the battery, unplug the O2 sensors, reconnect the battery (after 15 minutes of course) and then give it a drive. I will have to wait a few days to try that due to work, but I can give it a shot. You agree with the order and method I stated?

Does anyone think me buying the new O2 sensors was a good idea? Any harm in putting them in during this little dance I will be doing? Might as well since I will be under the car anyway.

Thanks for the tips 5000!

[BassMaster5000]

Bad O2 sensors usually cause a stuttering/bucking at part throttle. Someone correct me if I'm wrong, but your MAF takes over at WOT. The switching back and forth of an H pipe is something that is easy to do, but like you mentioned the O2 sensors could have been damaged in the process. Next time just do it yourself so you know the quality of the work done.

Your correct on how you want to disconnect them.

[ryanw]

C&l maffs are known to have problems. Also, is the maff calibrated to the 19 lb injectors ?

Maybe one of you injectors is stuck open.

Whats wierd is that with your fuel pressure being so high, i would have thought a code for runnng rich would have poped up

[BassMaster5000]

Originally Posted by ryanw Whats wierd is that with your fuel pressure being so high, i would have thought a code for runnng rich would have poped up

Would make sense if his O2 sensors are shot.

[fogged306]

If the o2's were bad, they would throw a code. If you're getting an 11 when checking for codes, I'd rule out anything wrong with any particular sensor. If you noticed the stumble when you put the CAI on, then take it off and put the stock intake tubing back on. It is possible that the CAI is skewing your MAF readings. Going back to the stock air box and tubing will rule that out. Does your MAF still have the mesh screen on it?

Also, if you think the varnish smell is coming from the charcoal canister, pull it and verify. That could be the source of your smell for sure.

[nolife]

Is the oil thin and smell like fuel? Check your FPR. Sometimes they leak internally and fuel squirts into the vac line. I'm sure you would have noticed that squirting out the vac line when you were adjusting it though.

[Ninety3Coupe]

The C&L came with the car (didn't know it was aftermarket until I went to replace it - car was very stock). I had purchased a Ford 70mm MAF part number F2VF-12B579-A1A. Then I read it needs to be used with 24# injectors. Since the car has always run with this C&L MAF on it, and I have cleaned it, I figured it was not the culprit. It has been a constant. I do not see a screen on it.

Will the new Ford MAF I bought work with my 19# injectors? If so I would rather have a Ford part on there anyway - I have heard of the C&L issues...

The oil is not contaminated, nor is the coolant. Both are clean.

The FPR is brand new and seems to work perfectly. I never saw anything odd or out of the ordinary.

I can pull the canister, but what would I be looking for? How does one determine if the canister is bad? Also, I would think the canister being bad would be the result of another issue, not the sole issue. Am I wrong?

I can replace the intake tubing and see if that helps I suppose. It's just a shame because getting that filter on in the fender sucked! lol Maybe this weekend I can swap that back to stock and run it with the FP set back down to 40psi. Then swap O2 sensors and maybe run them unplugged. That would at least give us a batch of new info to look at!

Thanks everybody, you guys have helped 1000X more than my last forum! I really appreciate the help guys.

[ryanw]

If the ford maff is factory, it should work, cuz the injector size is programed in to the cars computer. It only when you change injector size that you need to either have the cars computer reprogramed for the new injector size or you get a maff thats calibrated to the new injectors which basicaly tricks the computer. So basically a stock maff is programed for nothing, like if you pulled a maff off of a cobra mustang which came with 24 lb injectors, you could use the maff because the 24 lb injectors are programed into the cobra computer.... not the maff

For example if your c&l maff is calibrated for 24 lb injectors but you have 19 lb in the car, that will screw up the reading, making it run bad. Most of the time there will be a lable of the injector size on the maff or it will be ingraved into it.

C&l maff are known to not like extra air...lol they seem to work best in stock set ups ,do to where there flow tube is at. You should google..... problems will c&l maffs, youll have a lot of reading to do

[fogged306]

I missed where you had a C&L.. My bet would be on that meter and the cold air not playing nice. You could try clocking the C$L, which is rotating the housing to different degrees and trying it out. C&L meters are edge sensing units and any turbulence caused by a bend in a cold air can make them send dirty signals. Turning the housing can move the sensor out of the turbulence in some cases.

If that MAF is for a 94-95 mustang, which I'm almost positive it is, it will work with 19's. Those meters aren't calibrated for anything, it's the computer that is set-up for 19's. the 94-95 MAF is almost a direct replacement. I believe the curves are slightly different but I haven't heard of it being a huge issue and I've never seen a fox and an SN-95 curve side by side so I don't know how much of a difference they really are, but people use them all the time.

Like I said, if you've got no o2 codes, I wouldn't be looking there. Especially if your issue started after the cold air install.

Edit: ryan beat me to the ford MAF part

[ryanw]

Fogged got treed.....

I saw that he had a c&l maff in his sig, so you didnt miss any thing, Fogged