Author
|
Topic: 5.0 foxbody bucking @ low n high speeds
|
Svt Tony
¯
Member # 9959
|
posted
So when I finally tought I had my car running good (it did fir like 2 months) just last nite it started jerking/bucking like a freaking bronco it does it @ low n high speed but more noticeable @ low cruising speed so n e ideas?
1. New platinum ngk plugs 2. New roush 9mm wires 3. New rotor n cap (msd) 4. New Intake gasket 5. A shit load of bolt ons + NOS
-------------------- " u wanna play u gatta pay "
Posts: 1579 | From: 209 | Registered: Apr 2010
| :
|
|
JohnB
Tech Moderator
Member # 969
|
posted
Reset your base idle and TPS, then check fuel pressure at idle and under load.
-------------------- 1965 Shelby Cobra 1993 Cobra 2012 F150 Raptor 2020 GT500
Posts: 6523 | From: Orlando FL/Redding CA | Registered: Mar 2002
| :
|
|
Svt Tony
¯
Member # 9959
|
posted
got a new tps cleaned tb egr valve n still rpms chooping down in idle @ higher rpms seems fine can it be a vacuum problem?
-------------------- " u wanna play u gatta pay "
Posts: 1579 | From: 209 | Registered: Apr 2010
| :
|
|
gercolla1
¯
Member # 3068
|
posted
i had a prob like urs it was the injector harness ground wire mite be somethin to check tho
-------------------- Sf Bay Area
Posts: 2171 | From: Sampan San Francisco | Registered: Jul 2003
| :
|
|
Svt Tony
¯
Member # 9959
|
posted
yeah I ve been reading n there is a lot of posibilities as to what it can be so what is it that I should start checking first so im not just replacing parts it can get pricey n annoting so again Problem= idleing like crap n rpms chooping up n down also in cruising speeds it'll start bucking like a bronco
no new parts added lately other then plugs wires rotor n cap @ few months ago but run like a champ till few days ago n e help is apreciated
-------------------- " u wanna play u gatta pay "
Posts: 1579 | From: 209 | Registered: Apr 2010
| :
|
|
Adam5.0
¯
Member # 6995
|
posted
miss fire? check cap, rotor, plug wires could be burnt on header
-------------------- want something old and japanese
Posts: 1609 | From: Brentwood | Registered: Aug 2006
| :
|
|
Svt Tony
¯
Member # 9959
|
posted
Yeah I'll check the cap n rotor wires seem fine vac lines good too. Wd codes show up in the scanner even if the CEL don't come out
-------------------- " u wanna play u gatta pay "
Posts: 1579 | From: 209 | Registered: Apr 2010
| :
|
|
Svt Tony
¯
Member # 9959
|
posted
So I ve checked thr wires cap rotor n looks good sprayed some carb cleaner arond vac lines nothing still missfiring crazy idle n fogging when driving also tryed. New tps n used ica valve nothing the only thing I ve not mess with is the egr valve so far can't figure out what's wrong no check engine lite has come out yet friend says is timing cause if try to keep the rpms a bout 2500-3000 the needle choops up n down like crazy n also got couple of exhaust explosions back fire yesterday so n e help will be apreciated thanx I'm in ceres ca so if n e one wants to give a hand to a homie in need lmk thanx
-------------------- " u wanna play u gatta pay "
Posts: 1579 | From: 209 | Registered: Apr 2010
| :
|
|
CHP2981
¯
Member # 9240
|
posted
I had the same problem before and it turned out I had a vacume leak somewhere on the intake I just put on.
-------------------- No half steppin
Posts: 521 | From: Richmond | Registered: Jun 2009
| :
|
|
Svt Tony
¯
Member # 9959
|
posted
Already wasted a whole can if carb cleaner cleaning throtle body idle control valve maf sensor n checking for leaks I don't think is vac leak but who nos I'm fustrated just wana get it fix so n e help is apreciated thanx
-------------------- " u wanna play u gatta pay "
Posts: 1579 | From: 209 | Registered: Apr 2010
| :
|
|
CHP2981
¯
Member # 9240
|
posted
Yea I know it a pain buying things and it don't fix the problem. But what I did I just took the intake off cleaned the shit out of the surfaces got a new intake gasket kit and installed everything by the book. Good luck man I hate chasing gremlins.
-------------------- No half steppin
Posts: 521 | From: Richmond | Registered: Jun 2009
| :
|
|
Svt Tony
¯
Member # 9959
|
posted
Dont say I been at it for bout a week now n still no joy I ve taken the ontake out a least 10 times I had to check the plugs n wires replace the wires all together n nothing I having a guy mechanic come over see if he gets lucky thanx for ur input thogh.
-------------------- " u wanna play u gatta pay "
Posts: 1579 | From: 209 | Registered: Apr 2010
| :
|
|
Beasty5.0
¯
Member # 2935
|
posted
I had a similar problem once on my 91 GT, which was automatic at that time, it had a slightly off idle, but more importantly the damn thing would buck hard around the 2k-3K range, it was very strange. I went over everything like 3 times and eventually turned out to be the TFI distributor module. Good luck.
Posts: 1055 | From: San Francisco | Registered: Jun 2003
| :
|
|
SmokinLX
¯
Member # 1684
|
posted
Might want to try a known working distributer? Like John B said check fuel pressure at low speed's also if possible. Find a buddy to come by and work with You to get a different spin on thing's. I'm sure You have cleaned Your 10 pin connection's by now?
-------------------- Dont claim power if ya cant mile per hour. 10 second AOD
Posts: 4388 | From: East Bay | Registered: Aug 2002
| :
|
|
Svt Tony
¯
Member # 9959
|
posted
yeah I had a mechanic go over things once more. Car was stating fine then he came by she started acting up and thats how we/ he fonund out that the internals in the distributor were bad so I'm in the hunt for new/rebuilt/or good working one so lmk if n e of guys have one laying around.
-------------------- " u wanna play u gatta pay "
Posts: 1579 | From: 209 | Registered: Apr 2010
| :
|
|
Svt Tony
¯
Member # 9959
|
posted
So after checking everywhere for dizzys prices the best one was from Kragen believe it or not called ford dealer they wanted $259 for new one so I asked the guy since he obiously works there been a ford guy wd u buy the ford dizzy for $259 or msd for bout $300 he said msd hands down so Kragen had it for $259 with cap rotor n ing module so my girl is running strong again thanx for all the input
-------------------- " u wanna play u gatta pay "
Posts: 1579 | From: 209 | Registered: Apr 2010
| :
|
|