Idling Issues
10-20-2010, 01:00 PM
#1
3rd Gear Member
Thread Starter
Join Date: May 2004
Location: Richmond, VA
Posts: 614
Idling Issues
Hi all,
So I'm going to describe this as best as I can because I'm not the one working on my car - my mechanic is (speed shop). I did an engine swap and put in a 306 (bored), Trick Flow intake, Trick Flow Stage 2 cam, Twisted Wedges heads, throttle body, MAF, the works. To make a long story short, the shop that installed the engine in my car passed it off to the speed shop because they didn't tune cars, the speed shop did. The two shops know each other and have worked with each other before.
My car has been at the speed shop for quite some time now because when they try to tune it and fix the idle issues, they say it's "sucking air" from somewhere. Since they started working on it, I haven't gotten a good description of what's happening, but they're saying that if they pull out the MAF sensor it idles fine, but when they put it back in it runs like crap. Again, they keep saying it's "sucking air from somewhere" and that they've tried using a different throttle body, replacing vacuum lines, replacing gaskets, etc. Nothing seems to work (or so they say).
Anyone have ideas as to what might be going on? Has anyone heard of drilling a 1/8" or 1/4" hole in the throttle body?
I don't really understand what's going on with the car, all I want is for the thing to be fixed so I can have it back. I'm trying to figure out if I should just pick the car up and let it sit for awhile instead of wasting my money while they try to fix it.
Thanks! I'll try to provide clarification where I can.
So I'm going to describe this as best as I can because I'm not the one working on my car - my mechanic is (speed shop). I did an engine swap and put in a 306 (bored), Trick Flow intake, Trick Flow Stage 2 cam, Twisted Wedges heads, throttle body, MAF, the works. To make a long story short, the shop that installed the engine in my car passed it off to the speed shop because they didn't tune cars, the speed shop did. The two shops know each other and have worked with each other before.
My car has been at the speed shop for quite some time now because when they try to tune it and fix the idle issues, they say it's "sucking air" from somewhere. Since they started working on it, I haven't gotten a good description of what's happening, but they're saying that if they pull out the MAF sensor it idles fine, but when they put it back in it runs like crap. Again, they keep saying it's "sucking air from somewhere" and that they've tried using a different throttle body, replacing vacuum lines, replacing gaskets, etc. Nothing seems to work (or so they say).
Anyone have ideas as to what might be going on? Has anyone heard of drilling a 1/8" or 1/4" hole in the throttle body?
I don't really understand what's going on with the car, all I want is for the thing to be fixed so I can have it back. I'm trying to figure out if I should just pick the car up and let it sit for awhile instead of wasting my money while they try to fix it.
Thanks! I'll try to provide clarification where I can.
10-20-2010, 01:26 PM
#2
4th Gear Member
Join Date: Apr 2009
Location: N.C.
Posts: 1,893
These folks charging you money? When shop hasn't a clue...run away, flee, go elsewhere. There is not the skills needed in that building. Anyone can have a off day but not to get it as a priority for shop reputation is inexcusable.
10-20-2010, 06:39 PM
#4
4th Gear Member
Join Date: Apr 2009
Location: N.C.
Posts: 1,893
Do not drill hole. Did thay change injectors and match MAF? Silly question, had to ask. Is this a unmetered air leak that is being described? (gross vacum leak) Smoke available(not medicinal) at shop? Use low pressure air and kids bubbles to visual see leak.(redneck way) try to get some definite description of what is happening. Codes.
10-21-2010, 09:17 AM
#6
3rd Gear Member
Thread Starter
Join Date: May 2004
Location: Richmond, VA
Posts: 614
A couple quick updates and answers to questions...
No, I haven't heard the problem myself. I talked to the mechanic today who actually installed the engine and he gave me a lot more info than the speed shop, although he was talking way over my head and I don't remember all of it. In summary though, he says they've tried spraying and checking for leaks, checked vacuum lines and everything seems good there, checked and replaced gaskets, tried a different throttle body, basically reinstalled everything up to the manifold. Mechanic thinks it is an electrical problem - like a short somewhere or maybe a spliced wire that's causing problems. Mechanic is pretty frustrated with the speed shop for not asking for a different set of eyes earlier (they've known each other for 20 years), but it sounds like he's going to retrace the speed shops steps.
Also, another point of clarification is that the car will run when the MAF is out, but it doesn't run (sounds like it doesn't run at all) when the MAF is in.
Sorry I can't give anymore specifics, as a lot of it is over my head. I just wanted to get some ideas from people so I could try and understand what's going on and potentially help them out if someone has experienced the same issue.
No, I haven't heard the problem myself. I talked to the mechanic today who actually installed the engine and he gave me a lot more info than the speed shop, although he was talking way over my head and I don't remember all of it. In summary though, he says they've tried spraying and checking for leaks, checked vacuum lines and everything seems good there, checked and replaced gaskets, tried a different throttle body, basically reinstalled everything up to the manifold. Mechanic thinks it is an electrical problem - like a short somewhere or maybe a spliced wire that's causing problems. Mechanic is pretty frustrated with the speed shop for not asking for a different set of eyes earlier (they've known each other for 20 years), but it sounds like he's going to retrace the speed shops steps.
Also, another point of clarification is that the car will run when the MAF is out, but it doesn't run (sounds like it doesn't run at all) when the MAF is in.
Sorry I can't give anymore specifics, as a lot of it is over my head. I just wanted to get some ideas from people so I could try and understand what's going on and potentially help them out if someone has experienced the same issue.
10-22-2010, 09:24 AM
#8
4th Gear Member
Join Date: Apr 2009
Location: N.C.
Posts: 1,893
May be irrelevant but, one time in 93 has a 91 come to me. Ran like it was blown up, kaput. One of the MAF wires had pushed back into connector making partial or no contact. Put wire in place and came to life.
10-25-2010, 09:23 AM
#9
3rd Gear Member
Thread Starter
Join Date: May 2004
Location: Richmond, VA
Posts: 614
Thanks, Bubba. I'll keep that in mind when I talk to the mechanic. I took the car back to him so he can fix it and then I can finally get it tuned. It really does sound like it's an electrical problem at this point.
12-08-2010, 03:08 PM
#10
3rd Gear Member
Thread Starter
Join Date: May 2004
Location: Richmond, VA
Posts: 614
In case anyone is still following this, here's an update:
So I used 36 lb. injectors for this new engine, which they thought might be too much at first because they'd have to dial it down too low and they were a little worried about that. The fact that they might be too big was never brought up while searching for the "leak" problem until recently.
Me, my buddy, and the mechanic thought checking the o-rings might be a good idea, which led us to the injector size conversation. The mechanic said the 36's were running at 40% duty cycle. Long story short, I went ahead and bought the more appropriate size for my set up (24 lb.) which will obviously have new o-rings. I also have a 24 lb. sample tube for the MAF, so we're good there. I guess if nothing else, the new injectors should help the new engine run more efficiently. Any chance the injectors could be causing this "leak"?
So I used 36 lb. injectors for this new engine, which they thought might be too much at first because they'd have to dial it down too low and they were a little worried about that. The fact that they might be too big was never brought up while searching for the "leak" problem until recently.
Me, my buddy, and the mechanic thought checking the o-rings might be a good idea, which led us to the injector size conversation. The mechanic said the 36's were running at 40% duty cycle. Long story short, I went ahead and bought the more appropriate size for my set up (24 lb.) which will obviously have new o-rings. I also have a 24 lb. sample tube for the MAF, so we're good there. I guess if nothing else, the new injectors should help the new engine run more efficiently. Any chance the injectors could be causing this "leak"?