bogging following upshift

[danwheeler]

i've noticed I get a major power loss when shifting up after running out the previous gear. for example, i'm in first and run up the RPMs then shift to 2nd and sometimes it feels like it's going to stall. Am i just letting the RPMs drop too much or is there something I can do about this? I dont really want to powershift. it's a real bummer because everything is going well and acceleration is good, then you hit 2nd and boom - you're not going anywhere.

thanks,
dan

[hellraiser6919]

what rpm do you shift at?

[danwheeler]

not too sure - no tac. would it make the problem worse if i shifted at too high of RPM?

[gdawgs]

Once you're in 2nd, and you step on the gas, does it accelerate ok then?
I'm not sure I'm understanding the problem.

[danwheeler]

it accelerates ok after a second or two but until then it's totally flat. the RPMs are dropped and it's really slow to get going once i've shifted into second. it doesn't happen all the time and is worse when its cold

[gdawgs]

Fuel injected or carb?

[danwheeler]

Fuel injected 93. it runs pretty well otherwise, just this specifically seemed a little bit off. wasn't sure if it was my driving style, the nature of the car or something was actually wrong.

normally I have very good low end torque so it seems weird that it would be so flat in 2nd. maybe something is happening when it goes from high RPM to low RPM and has a hard time getting going again after it has dropped.

[gdawgs]

Sounds like something funky is going on. A few more questions.
Does it do it in all gears or just second?
Does it only do it if you rev it up real high before shifting?
How about if you just putt along and don't rev it very high before shifting.
Once you're in second, then it starts working again, what happens if you slow way down, then floor it(never taking it out of 2nd or pressing the clutch)

What have you replaced recently?
If nothing, I'd start with the basics.
Check for vacuum leaks. Pull the spark plugs and see what they look like.
Replace plugs, wires, distributor cap/rotor, air filter, etc.

[FB71]

sounds like a dead spot in your VAF meter. This happened alot with old (mid 80s) Escort GTs and Merkur XR4Tis. If you have access to another VAF, swap it and see if the problem goes away or even just gets better.

[danwheeler]

thanks guys - i'll take it out today and try playing with it a bit to see if it's doing it when i stomp on it in 2nd while at low RPMs with my foot off the gas. it's most noticeable going from 1st to 2nd and a little less noticeable from 2nd to 3rd and even less so from 3rd to 4th and haven't noticed it from 4th to 5th.

i'll also test it with lower RPM shifting and higher RPM shifting to see which is worse.

i haven't replaced anything recently except for a new stock muffler. I jsut got the car a week ago and somebody had put a massive magnaflow muffler on it so i took it off and put a normal one on. it should be pretty much stock.

I believe cap/rotor and fuel filter were replaced very recently by previous owner. haven't checked air filter or plugs or plug wires so i'll do that tonight.

thanks for the help guys - i'll have more info tomorrow.

[97 Aspire 5 Speed]

My 97 Aspire does the exact same thing!! I swear it feels like the ignition timing is retarded for just a few seconds after you let the clutch out after each shift. With 1 - 2 being the most noticible!

It doesn't seem to do it as much if you're just tooling around shifting, but if you wind it out in first and then shift, it just falls flat on it's face for a second or two and then goes.

And I thought I was just going crazy!!

[danwheeler]

yeah, exactly - flat on it's face for just a second or two. so weird. i just went out and got some plugs and wires and a new air filter. we'll see if that helps at all. i'll try to find a VAF if none of that works.

[oxbrain]

I've been having a problem a lot like that too. It happens when I'm accelerating hard and shift or when I'm coasting and then accelerate hard. It just feels like there is no power at all. I have changed VAF's and it hasn't seemed to make a difference. Problem carried over from the B3 to the B6 as well.

I was thinking it was a fuel pressure issue.

[danwheeler]

oh yeah, i was going to mention - maybe the fuel pump? it seems sorta familiar to a problem i had with an audi a long time ago.

[97 Aspire 5 Speed]

And just as a side note, when I got the car a few months ago I did a full tuneup:

Plugs
Wires
Cap/Rotor
Air Filter
Fuel Filter
O2 sensor

And no change in the symptom... but a huge change in the performance... I think it had the original plugs! :shock:

I have a MAF and OBD-II. I know Ford retards their timing on the shifts of automatics, and I would not be surprised if they don't do it on these cars also.