JDP6693

iTrader: (1)

Okay, so my vert runs like a champ, especially when it's cool outside. It's got just as much power as any other stock vert 5 speed, and it runs smoothly. Until it gets hot. There are times during daily driving where I will park it for a few minutes, and when I get back in the car and start it, it revs up a tad like it should, and then promptly dies if I don't get on the gas. I don't have to stomp it, I just have to pin it at around 2k rpms for about three seconds, and it sounds like it's choking or misfiring a bit. But as soon as I let it go to idle, there are zero issues. That, I attribute to the common hot start issue that I need to look into more. That bugs me, but I only told you that to see if that issue is related to the issue this thread is about:

When the car is good and hot in daily traffic, and I pull up to a stop light, the car is really sluggish when I pull off. It's like it's not breathing well, and trying to bog down and die. Its nothing extreme, but I have to give it a little more gas and feather it a bit more than normal. It feels like a poor breathing car with a shot clutch, but only when hot. Any other time, the car is crisp and quick. Only when it's been hot for a while does this happen. I don't know if something is wrong, or it's just the heat but it doesn't feel right. It's completely stock besides the RB catback and I put a reman'd S5 motor in about 10k miles ago, along with a new clutch and throwout bearing. The swap was done right. So, am I looking too far into things, or do I need to invest in an intake, or what? Please, help. I'm stumped here.

~Josh

Keeble

iTrader: (3)

i would guess that you have leaky injectors and it floods once its off.

but somebody else might chime in with a better answer

JDP6693

iTrader: (1)

That makes sense. I didn't crack open the motor during the swap, just pulled it out and dropped it in the new one. But would that cause the same bogging, choking issue when it heats up?

j9fd3s

iTrader: (3)

since its an S5, we can go down a list...

1. check engine light on? any codes? if there are, look there first, if not is ok.

2. since its a temp problem, maybe it makes sense to look at the temp sensors, there is one for the coolant, and two for air, one in the AFM and the other in the intake

3. i think maybe checking fuel pressure might be a good next step. maybe the FPR solenoid is bad, or the vacuum line isn't hooked up correctly or something

JDP6693

iTrader: (1)

Nope, no codes or errors or lights aside from Oil Level every 6 weeks or so. Maybe the sensors and vacuum lines need a good checking/replacing. I'll look into that. Thanks!

JDP6693

iTrader: (1)

Okay, so the past two days have been pretty successful, I think. I fixed my alarm issue, top issue, window issue and found both my tranny leak (boot is ripped, leaking oil down tower and spinning around on driveshaft, throwing crap everywhere) and an oil leak in the oil cooler lines (to be replaced soon). From what I've looked at today, all the wires, hoses and sensors in the engine are in working order, so I'm going to rule out sensors. I already replaced the coolant sensor when troubleshooting the original coolant issue on the old motor, so it can't be that, but I still need to go through the intake system really well and check it out. There is one thing bugging me still, though. This morning, starting it cold the car revved to 4k, higher than normal, then went to 2k but then back up to 3k and did the full cold-start cycle like it should have. Kinda seemed like a vacuum issue of some sort, but every other time I started/drove the car it ran flawlessly, and I was running all over town in it. So, a little stumped still. I'll check out the intake system, but how do I go about checking the FPR solenoid/vacuum? Can't seem to find a diagram or troubleshoot anywhere.

JDP6693

iTrader: (1)

Alright. Got a new theory. I think my bogging issue is caused by the transmission, not the motor. When it's in neutral, it revs, sounds and acts as healthy as can be regardless of the temperature. When I shift to first, however, and let the clutch out at a stoplight, the car acts like its being smothered. And now, as I've noticed, it doesn't have the same pep when I het second that it used to. Not to mention that second has been grinding a little bit recently. Also, when it's cold the car doesn't like to go in reverse, and when downshifting and stopping, it's hesitant going back into first. Like I have to push past a detent to get it into the gate, almost. So, I'm gonna do a tranny flush and look for anything out of the ordinary and see what happens.