Hesitation and bucking

[jduke0308]

Ok so i have a hesitation and bucking issue at all rpms. Revs freely and normally while sitting. The moment i go to take off and release the clutch it loses power and barely wants to move. once i finally get it rolling it bucks and hesitates. Cant even drive it now. Where should i start digging into? Also i dont have a datalogger unfortunately.

New parts on the car
OEM coolant temp sensor and new wiring
oe fpr
new oem valve cover and oem gasket
new plugs properly gapped (also have older magnecor wires)

 

[Yao]

does all wheels spin freely?

 

[MellowVR4]

Put it up on all four jack stands and see if all of the wheels spin..

 

[prove_it]

Get a logger. You need to see what the ecu sees.

Check the wheels for free spin. If that's good, then you got a drivability issue. That's where a logger will help a lot. Otherwise, to me it sounds like a possible boost leak, bad maf or bad fuel delivery. All three issues can cause a decent idle and free rev, but when load is applied it falls on it's face. Although a big boost leak will cause a bad idle too.

 

[jduke0308]

Thanks guys, put her on all four to put on my exhaust and all 4 wheels move fine. Bought a data logger from 1glink.com that will be here tomorrow so Friday I'll be able to dig deeper.

 

[prove_it]

Do you have a known good MAF you could try?

 

[jduke0308]

I may be able to get ahold of a maf, when i do ill check that. SO i got my logger, not quite sure how to use it quite yet but my 02-f value is 3.49 at all loads. Is this normal? Also ftrl 139%, ftrm and ftrh are approx at a 100%.

 

[GSTwithPSI]

TPS bad or out of adjustment would be my guess. Have you calibrated it lately?

 

[vr4g63]

The only time I've had similar symptoms is when I ran out of fuel. It would start, idle and rev fine, but as soon as I put it in gear and tried to go it would loose all power and ability to rev. I'm sure you're not (almost) out of fuel, but it makes me wonder might also be a fuel delivery problem, like maybe one of the fuel filters.

 

[jduke0308]

Has a newer fuel filter in it. Going to test the tps and isc saturday. Also replaced injectors and maf with known working ones to no avail.

 

[Coltsfan]

Sounds like idle switch to me. If the ECU sees idle switch activation it will go into decell mode and cut fuel at all kinds of random intervals while driving.

 

[jduke0308]

Well think i just found the problem. ecu started smoking. checked ohms on isc and the were high. So ordered a new isc and got a spare ecu as well. Sucks because the one that fried was an eprom one /ubbthreads/images/graemlins/bawling.gif

 

[jduke0308]

Well only thing we found out was my buddies isc was shot and fried the ecu while trying to diagnose the problem. So I'm still having the same problem. Also put a new isc, iac, and tps.

 

[jduke0308]

Also anyway to add videos? Triedo photo bucket but it won't let me due to video being to big even though it's a short video.

 

[FlyingEagle]

Youtube and link here.

 

[highrpm666]

I would be willing to take at look at it and help diagnose the issue. I'm over in Englewood. Pm me

 

[jduke0308]

Here's a video of what the car is doing.
click