Thread: Bandook's 01 Imp, top swap-ified

Wideband is fine. Startup is fine then super lean and misfires as soon as it goes CL. Little spray in throttle body and it smooths right out. No Vac leaks.

Why would my wideband make my car run like crap

Originally Posted by bandook

Why would my wideband make my car run like crap

it cant, but it can read wrong, every time ive had a wb sensor go bad it read lean.

Ah ok. Good to know! It does respond to spraying the filter though. I ordered an OEM O2. This one doesn't show much activity. Ordered last night on Amazon and supposed to be delivered today. I love living close to a warehouse.

O2 is in, car is running great again. Here's a healthy O2 at idle. And a working wideband, btw :P



I'm still seeing boost drop off. What I thought was belt slip i'm thinking now is a "boost leak"? Don't think I have any vac leaks, though i'll probably smoke it again to see. Or map sensor flaking out. Dunno.

Here's what happens that made me think belt was slipping. Hit 12.5 lbs at 4k, then drops to 12 lbs at 5250.





Just had a thought while typing this. Woould haveing too long of pushrods cause this? I've always had that in the back of my mind because when I put the cam in I was right on the edge with stock pushrods according to my measurements. THinking the lifters are pumped us and just barely holding a valve open. Or not. dunno. I'm a dummy. Car runs great otherwise.

you have all your tm files maxed out? when i did a gen 5 swap id make like 13 psi in first, then once in second, 5 psi and it just held there no matter the rpms. found one file i had not touched and that made it build full boost.

Yeah tune is good. Same tune except for maf/timing settings that I used before cam install. And I was maxing out map sensor.

Well, it shouldn't have.

right, should keep building psi till you red line. lower after the shift and then pick it back up as the rpms go up again.

Whoopsie!



Not sure that's the culprit yet, but it probably doesn't hurt to have a bolt there.

Here's a few pulls. The first two i shifted into 3rd at wot. The boost slowly falls off then peaks as it shifts. Just from more load on the shift I suppose. But I scaled the map and boost so you get a better look at what's going on. Car doesn't feel down on power, still has the same 50hp it's always had, I just like troubleshooting little issues like this.

















BTW, you like that timing? Haven't seen any knock. Meth plus E85 makes for a much slower burn. Just recently heard on PFI speed that alcohol cars need to run north of 60 degrees advance.

only difference i see with the boost is the rpm's are lower. your not gonna hit 13 psi and keep it there through the shifts.

i know a guy who had his car running 28º wot fsic 2.55 gen 5 and e85. made like 15-16 psi iirc. soooo maybe try a few more degrees. might like it.

and id have to think e85 with meth is like 115-120 octane now. let the old girl eat.

Swapped in a map sensor, same thing. Confirmed by recording my boost gauge that it's falling off. I'm leaning to valve float causing the issue. Boost drops more as it gets closer to redline. And like a dummy I used stock springs because I didn't have the modified retainers for the new springs. Was in a hurry because it was getting cold out and I was just over all the crap I went through with my head's and the shop.

Anyhoo...I'm calling it valve float. Not crazy about swapping springs in the car but I've done it before. Dunno when I'll be able to swap em because I'm doing a bunch of work in the house this summer. Still working on master bath, then floors throughout, new trim, doors, paint everything, ....but I want to do the car now Dang priorities.

Ok maybe I was jumping to conclusions. Remember, i'm a dummy. It's possible it could still be belt slip. Here is a 2-3 run with smaller pullet on idler.




And here is after putting on the bigger pulley.



Doesn't it look like it's holding a little better? Seemed consistently a little higher. If I can find a belt that just a little shorter I'll try that. Also I'm using the used tensioner I bought here, no idea how old it is. Never had a new tensioner. Think I'll try that next. I guess 8-rib is all that's left. Anyone got a set? And it seems to like the bump in timing. Also dropped plug gap from like .50 to .40. Thinking maybe it was missin' up top causing the boost loss. She feels real good, I just can't rest until this boost issue is sorted, lol. Hopefully I don't tear it up before I get to the track. Plan on going soon to see what this cam has done for me.

Better comparison

I revved it out a little higher. Definitely getting valve float. Oddly enough though, the boost jumped back up towards the end. I'll post a screenshot. Have to get the new retainers and springs in soon because I want to hit the track. I'll probably get a smidge shorter pushrods, too.

When doing springs in car, is there a better tool to use than the two jaw thing that I have? I've found its its its easy to have them less than perfectly straight and that causes the valve stems to get nicked. Do the ones for the LS heads work on these?

just seen a vid of a guy doing them with a roofing flat pry bar, rocker bolt through the hole to pull nails and the two claw ends pushed the retainer down.

Welp, springs and rods are in and car is running good. However....boost issue remains, lol. Dagnabbit! I mean, I've been wanting to do springs since I put the cam in. Valve float is gone. Hit 6300 rpm no issues, but need to turn down shift point a bit, still playing with those tables. Here is one of the first pulls:




I mean, car feels better than ever. It really seemed to like the timing, up to 28 degrees. Not a lick of knock. So i thought maybe it's still belt slip. Went and got a can of belt conditioner because why not, it's about all i can do. Here's after a heavy application:



It looked like it picked up a little.



..........EDIT........

So I can't use the image hosting site I normally do anymore? Well crap. Anyways, one thing I noticed is that the map goes up and down a bit, won't climb, but it consistently plateaus at 184 kpa. Before and after belt conditioner. It's a common number in all my logs, It's a little more than 12psi. So maybe it's a boost leak issue. Could be a bad S/C gasket i guess. I have no way to do boost leak test, I'll have to figure something out.

What website is best for image hosting? I really liked ImgBB