speedfreak81

Being relatively new to these cars, I'm not sure exactly where to start......I guess with the symptoms.

Picked this car up in August and minus the excessive start time (usually 4-6 seconds or so) it ran great. Well, lately that hasn't been the case. It has a Bursch test pipe on it so I was somewhat used to the smell of gas from the lack of a cat. Lately the car has started to smoke, mainly coughing on start up and at random points when I'm under boost, or on decel when I come to a stop at a light. The smoke stinks of gas and oil and is pretty embarassing. I noticed a lot of oil buildup around the silicone hose that connects the MAF pipe to the turbo, as well as the intercooler hard pipe that runs to the throttle body. It looked like it was building up around the bottom of the silicone boot that connects the throttle body to the hard pipe. I thought maybe it was coming from the intake, so I pulled the boot and checked but the inside of the intake manifold is bone dry so it's coming in from somewhere else.

Also, the car has developed a misfire and high idle coupled with the fact that on cold starts it sounds like it wants to die. After 4-6 seconds of cranking it finally fires, revs up to about 1600rpm, then drops back like it's going to die, then sort of sits there sputtering at around 700-1000rpm. If you roll into the gas pedal it immediately coughs like it wants to die. This has me thinking vacuum leak, and my autometer gauge reads between 8-10" of vacuum on cold starts, and after the motor is warm it reads right around 15".

This car only has 50k miles on it, and Jeremy Himsel installed all new vacuum lines via the Lindsey kit a little while back.......so I'm having a hard time believing it's the lines themselves. Unfortunately not being familiar enough with these cars, I don't know exactly where to look to see if maybe something has come unconnected other than a quick visual inspection.

I've been doing a bunch of my own research on the forum, and thought maybe it might be the TPS sensor, or the ICV? I don't want to just start throwing parts at it until I get some possible insight from people more familiar with these cars.

Anything anyone can point out would be GREATLY appreciated!

-Brian

Just for reference, mods on the car are as follows:

Vitesse MAF kit and chips
55lb injectors
manual boost controller @ 16psi
Bursch test pipe
SFR exhaust
Tial 38mm wastegate

JohnKoaWood

Oil in the MAF to Turbo pipe is blowby from the AOS, a catchcan will help, but it would be better to figure out WHY it is blowing oil out of the air oil seperator... compression test / leakdown test will highlight where your crankcase pressurization is coming from (piston rings are suspect)

Do you have a wide band O2 sensor installed? If so what are the readings at idle, on boost, and on decel? What about any differences between when it is running "well" vs "coughing"..

It sounds to me like there may be multiple issues...

1) DME temp sensor (test per clarks garage), if it is bad you will swing rich all the time... bad rich...
2) TPS adjustment
3) Sounds like you are running overly rich (WILL cause ring damage from cylinder washdown, resulting in crankcase overpressure from blowby), check the MAF settings, have it tuned using a WB O2 to verify mixture...
4) Sounds like you may have a vacuum leak or bad ISV... the ISV can be tested (clarks garage), easiest way is to unplug it and see if the bahaviour changes...

Any way you could bring it a little to the south of you (I am in Stafford, Aquia Harbor to be more specific), or into a familiar shop up there? I usually have pretty fairly open weekends... and a whole pile of spare parts just sitting right now...

Ski

It could be a number of things, do you have the SMT-6 piggyback on the car? Check the wiring to make sure one has not come undone.

Check the hose to the ISV and then ISV to IC pipe, make sure it's not pinched or become pinched.

+1 on the compression test and leakdown. If you've played with the car REAL hard or missed a shift, you may have bent a valve.

speedfreak81

I would LOVE to bring the car down and have you check it out. What is this weekend looking like for you? I could probably get down to Stafford in less than an hour.

Also, I had a compression/leakdown test performed before I bought the car 5k miles ago that showed 2% across all 4 cylinders.

-Brian

JohnKoaWood

PM Sent

speedfreak81

Just a thought, concerning the vacuum issues on cold start. The behavior it exibits in some way reminds me of my old LT1 fbody. Those familiar with these cars know about the rubber elbow that connects to the throttle body. It was not uncommon for these things to tear or rip, or become crimped on the bottom side because of misinstallation. Anyway, if this happened it would create a pretty nasty immediate off idle stumble, similar to what I'm getting with the 951.

Anyway, what about the fuel vapor diaphram? Was reading up on Lindsey's website and this is word for word what they described, "Over 50% of those tested are faulty. Since it's connected to a vacuum hose that connects to your throttle body, it's the equivelant of a vacuum leak at the throttle body."

Only problem with this is why it would only sputter like that when the engine is cold, and not once it heats up?

fast951

Most everything has been mentioned already.

Check and fix (not in any order)
- Vacuum leaks
- Fuel pressure (Fuel Pressure, Regulator, hose to Regulator also check the dampner)
- Ground connections especially at MAF
- DME Eng Temp sensor & its wiring
- TPS
- O2 sensor

F18Rep

John is the man but my bet is that your TPS is full of oil, which means it may test good at times but be bad intermittantly.... Deal with that first as it is easiest... Bruce

speedfreak81

John,

You may be familiar with this car. It belonged to a former rennlister, Steve Ventura from Phoenix. I spoke a bunch with Jeremy Himsel a bunch, met him when I flew out to Phoenix to pick up the car, and he had done a bunch of the work to the car, said you would recall it.

-Brian

fast951

Brian,

I do not recall the car (no reason to), But I do know Steve and Jeremy both are stand up guys. Jeremy does good work. He usually offers on-site lifetime warranty on his work, have him fly over to fix it. His father uses his free lifetime support all of the time.. LOL.

I forgot to mention it in my earlier post. Where is the oil coming from and why? This is not normal.
Oil on the MAF will mess it up, I would clean the pipes and MAF. Still you might have other issues..

speedfreak81

Oh I don't think there was anything done incorrectly by Jeremy. He certainly knows what he's doing. Whatever is going on with the car is more than likely something that has just happened by cocincidence since I've been driving it a good bit.

JohnKoaWood

DME temp sensor is the only one I dont have sitting at my house, I delivered my new sensors with the rest of my engine a few months back...

I have a BRAND NEW TPS on my intake, we can swap it in if we need to on Saturday..

fast951

You can use a resistor in place of temp sensor (for testing only!).

fast951

I was joking about the Lifetime warranty...

Usually when the car goes from running fine to not, something happened. As long as you can reproduce the problem, you should be able to find the cause. If you can take the car to John, it's sounds as the best solution. Just make sure he doesn't strip it like he did his own car

speedfreak81

Yeah, I think we're going to meet up on Saturday sometime. And there will be no stripping involved!......Unless maybe I decide to bring one of my lady friends with me.