fellows i need some help on this one .i have a new 305 h.o.,it revs to 4500 rpm and stops revving,it sounds like it runs out of fuel.
parts replaced with engine change:iac,tps(set at .54)egr,rotor,cap wires,plugs.it has an afpr ,all new gaskets on runners and plenum.the only thing i did during swap is on the plenum ,behind throttle body i cut down the 2 ridges& smoothed the walls.
if i hold the throttle 3/4 it will rev to 5800 ,no problems at all in first gear ,if i floor ,it drops back to 4500 rpm,wont shif at all. let off throttle 1/4 inch ,changes gears ,spins tires ,revs to4500 ,does the same thing again in second gear.ive played with the timing.i ve carried it up & down ,makes no diff.ive taken off tube to air filter, no diff.unhooked egr & plugged no diff. checked fuel press.,tried it from 39 lbs. to 50 lbs., no diff.little diff.in throttle response.for ref. car has 305 h.o.,700r4,4:10 gears,engine is bored 30 over ,all new parts.tpi. thanks for any ideas on this prob.(almost thought about selling),but not yet. thanks again ,jimmy

 

Since there's no responses, and I'm pretty bored at the moment, I'll take a WAG.

Is it possible the throttle is being opened too far (butterflys going past horizontal) at WOT?? That would explain why it runs stronger at 3/4 throttle than WOT, and might also cause the tranny cable to be out of whack too.

 

ive thought of that too ,and the winning answer is ,no.wish it had been thanks,z i also checked&rechecked the valves,no fun ,ive loosened the gas cap just to see if it helped,ive unhooked the battery cable,left it off overnight to no avail.i have adjusted the detent cable also,all ideas appreciated ,may be something simple.thanks jimmy.

 

Sounds like the tps. Did you try diff positions just for grins?

 

at this point,im ready to try anything.cant hurt,nothing else has worked,thanks badride5.

 

bump

 

How old is the cat converter?

 

converter is about 3 months old,its a hi-flo.i took the fuel lines undone yesterday and took the air hose and blew through them,and the fuel filter,seemed fine .hooked it back up ,pump ran for like 5 secs.fired right up.thanks for the input ,Stekman.if anyone has an idea at all,please post it ,thanks in advance,jimmy

 

does it do this if revving in nuetral/park or just when driving. the fact that it won't shift at full throttle sounds like it may be tranny or kickdown cable related. My only other thought is that there could be a dead spot in the TPS. Does it get a voltage reading all the way through it's travel?

 

Some of the things you have mentioned, such as moving the timing back and forth, raising or lowering the fuel pressure within that range, and disconnecting EGR vs. a hooked up EGR should make for a hell of a difference.

Check engine light on by any chance? You might be in limp home mode.

You need to have your timing set to 6 or 8 degrees with the EST connector disconnected, fuel pressure set to 43 psi, and EGR hooked up properly. In addition, make sure your fuel pressure holds for several minutes with the key on, engine off.

Your shifting problem is either tranny or TV cable related. Try adjusting the TV cable as per a repair manuals instructions.

By the way, you can't have a 305 H.O. with TPI. H.O. was reserved for the L69 which was a carbed 305 produced until 86 or 87 (I forget... something around there).

 

Have you checked TPS voltage throughout the throttle range?

 

first ,thanks,stekman,hodge,92blue.ive adjusted the detent cable quite a few times,the timing is @ 6* the tps is new,set at .54 ,checked it doesnt fall off at all.as for the revving,it does it in neutral,driving.if i floor it revs to 4500to4800 rpms .its hard to explain:it sounds like a carb. eng. when the lifters start to float at high rpm. when it does get to 4800 it doesnt loose many rpms at all.ive set & reset everything i can set.timing ,tps, iac,detent cable,fuel press.,valves. i almost sold it the other week, then i said ,nope this isnt going to whip me ,well atleast not yet. thanks for all the help fellows.hey if anyones has an idea & doesnt want to put it on here, you can e-mail me at jimmysfastam2005@yahoo.com thanks again

 

When you say that it revs up fine at 3/4 throttle, are you doing this in D, letting the transmission do the shifting?

What happens when you rev it while shifting manually?

 

i would get a wideband on it. it sounds like as long as you're not in P.E. mode it rev's fine. getting a wideband on there is going to tell you if the P.E. mode is sending it way rich or not adding enough fuel maybe from a fueling problem. i'd also check fuel pressure as the condition is occuring.

 

stekman, it does it either way,itll even do it in passing gear ,can be running 55 and stomp it drops back to third revs good until 45-4800 stops revving until i let off just a little, changes fine.maybe it needs a choke. haha jimmy

 

Have you tried taking off the fuel filter and blowing through it with your mouth? If it's hard to blow through, replace it. It probably needs replacing anway. These fuel filter are known for clogging up in 6 month to a year. I bet if everyone on all of these boards would check the fuel, they would find out that they are clogging up and that will give you a lack of performance and solve a lot of problems. My 99 Suburban would not rev pass 3500rpm until I change the fuel filter and it's take the same filter as our cars do.

Another thing, what cam and heads are you running? Cheap heads and peanut cam won't let you rev pass 5000 anyway.

 

Sorry I don't have an answer for this problem, other than to tell you that you may have a bad fuel pump, clogged filter, or the torque converter is going bad.....as for this quote, I'll inform you that yes indeed there was a 305tpi ho. The proof is on the sides of the TA I am buying, it was origonally a 88 TA, 305 F.I.(tpi) H.O. I will provide pics this weekend to show this....I just have to buy the car first. This car i am getting is pretty much fully loaded. I am new here, and I am just using my future car as a reference.
Andrew

 

THANK YOU 2-toneTA,i had done an rpo on tgo before ,the numbers in the rear glovebox said it has a 305 H.O.when i ordered the new engine i ordered a 305 h.o.please post your pics.also thanks vincentz28.the trans shifts perfect,until i floor it ,no slippage,at all.i have taken the air hose and blown threw all lines ,filter and lines to the tank,had the fuel cap off,you could hear the air when it went thru the lines into the tank.thanks zippy,fuel press. is fine stays where i adjust it to during this.as for the wideband ,how do i hook up a wide band ?,dont they have 4 wires? my o2 only has 1 wire. im kinda like you and others ,maybe its not getting enough fuel,really doesnt sound or act like too much fuel.thanks for everyones input,if by some chance i dont thank someone ,i dont mean not to . oh ive been doing a lot of reading on here: other forums. can anyone explain limp home mode to me ?.if so,do i have to reset something? also read something about ,megasquirtII, does our/my car have this?again i do appreciate all the help.this is a neat site ,lots of nice people with great advice.

 

Limp mode is basically a very base setting for engine management. Like "X" amount of fuel, "X' amount of spark. Just something the ECM has to fall back on in case trouble arises. Judging by your description, you aren't running in limp mode (you'd feel limp mode).

A wideband o2 sensor is an addon sensor. IMO, not really worth the investment quite yet.

I agree on the suggestion of hooking up a fuel pressure tester and watching the fuel pressure when the problem is happening (i,e at WOT).

The torque converter is another thing that crossed my mind.

 

thanks stekman,i had read some articles on ,now i understand it .the wideband heats up doesnt it ? if yours doesnt.dont think its the converter,comes off the line like a champ,spins both tires in first& second,shifts real hard in third.if you dont think i need it ,i dont need it.thanks man,jimmy

 

No there wasn't. All 305 TPI engines had RPO code LB9. All 305 H.O. engines were carbed and had RPO code L69. There was no L69 offered in 88 either.

Having emblems or decals doesn't prove anything. Those are easily added or removed.

 

The closest thing to a 305 TPI H.O. would have been the G92 equipped 5 speed cars.

 

http://pageperso.aol.fr/sdgreyefdbv/...echnik/01A.htm

blue92 go to this link, look at lb9 ,it says tpi ho does it not ? im not saying youre wrong,but neither am i according to this,theres an lb9 in my car.thats why i said it was an ho. zippy g92 has something to do with rear gear performance: confused:

 

I think you are confusing a heated o2 sensor with the wideband. With a wideband you can view your AF ratio more or less. That will tell you what's going on on the top end, whether or not you are leaning out or what. These do have advantages in that it can (and probably should, if you get one) be used as a normal gauge as well, not just as a diagnostic tool. However, like I said, save this until all the other options and tricks at your dispense have been exhausted.

As far as a heated o2 goes, as it's name implies, it's heated, meaning it's brought up to its operating temperature faster - that's all.

I would start with a rail pressure test while the engine is bogging down and see where that takes you.

BTW you have a private message.

 

the G92 equipped LB9's included the same camshaft as the L98 giving them 25 more hp. the LB9 in standard form is far from an H.O. it may be listed that way, but that's just from someone typing that in there. an H.O. V8 has more than .400" valve lift for a cam.

 

http://pageperso.aol.fr/sdgreyefdbv...technik/01A.htm

Now there's a real "expert" on what constitutes "HO" or not.... a private AOL user in France.

I'd leave the whole "HO" business alone, if I was you. It's just buzzwords and drivel. Maybe you should call it a "early Vortec HO police interceptor" model. Kind of makes you (and people that want to argue about whether it's "really" a HO or not) look sort of stupid and self-important.

Seriously, looks to me, from your description, like either your WOT fuel map is wrong for your new engine configuration; or your TPS voltage isn't going high enough at WOT to get into it.

 

I had a simliar issue long ago when I first got my car. It would run great until about 3500 rpms then run out of fuel to keep it going. Turned out to be the old fuel filter. Replace it and see if it goes away. Cheap part and should be replaced periodically anyway.

 

Did you change the MEMCAL/chip in the ECM after the motor swap?
I've heard of this happening when a V6 memcal is used on a V8 application. The fueling calculation is different in the code.
Its out in left field but I keep thinking about mentioning it anyway.

 

i really dont give a holy rats tail whether its an ho or not i just want to fix my car .i didnt start the argument anyway.that said: can we get back to what may be wrong with my car.thanks jimmy

 

Going back to the fuel filter, take it off and blow through it with your mouth not with an air hose. If it's hard to blow through or it take some pressure to blow through it, it's bad. Change it anyway. I know you haven't change it in awhile. Go back to my eariler post. Trust me. I have been dealing with 3gens since 1987.


305 H.O carb cars were made in 84-86. Some of the 5 speed cars had factory 3.73 and some autos had 3.42 and 3.73. The 84 H.O. was rated at 190hp. The 85 an 86 H.O. rated 215hp.

 

Not to be rude or anything, but people have been suggesting tons of things to try to help you out, and you are ignoring it all. You keep repeating what the car is doing, instead of asking how to go about testing other peoples suggestions. It seems like you are hoping someone is going to jump in and tell you exactly what part you need to change. Thats not going to happen. It seems you are putting in less effort into finding the problem than most of the people that have made suggestions to you.

With regards to not caring about the H.O. issue, that doesn't make any sense at all. You think its significant enough to list as your engine type right next to your post count, but don't care if what you wrote is wrong? You took the time to try to prove that there is a TPI H.O. by quoting another site you found online, but at the same time, you don't give a rats tail about the whole thing?
I don't understand...

 

THANKS, to everyone that has replied to my post.i DO appreciate ALL the suggestions given.T.Y.,zz28zz,T.Y.badride5,T.Y.Hodge,T.Y.Vincentz28,T.Y.2-toneTA,T.Y.Bluers91,T.Y.JP85SS,T.Y.Stekman,YOU GUYS ARE GREATand have been very helpful but, i am asking that this POST BE CLOSED PLEASE.again THANKS,MEN.

as for Sofakingdom,& Zippy i thankyou for your suggestions,i tried them also.NOW to 92 blue ,if you WOULD TAKE TIME TO GO BACK & READ ALL MY POST ,YOU WILL SEE THAT I DID TRY ALL THAT WAS SUGGESTED.even by YOU.and i did say THANK YOU .i didnt post on here to cause an arguement .i said it was an ho because i thought it was,MY mistake,its people like YOU,zippy& sofakingdom,that make it hard for a NEWBIE like me to want to post on here.were/ im not stupid, we/i just dont know as much as some people on here.thats why i posted on here.


please close this post,thank,you

 

I can't close the post, but did you find the problem with your car?

 

no sir, i didnt fix my car . i may repost at a later date ,thanks again to everyone .jimmy http://www.cardomain.com/my/y

 

ok with engine off check the tps at wide open throttle the tps should give a 4.0 volts or 4.5.and at idle should be .05v i think i may be incorrect and.also check vacume you can get a vacume gauge at napa for 20.00 or higher hook it up to small port closest to the intake as possiable.start the car read what the gauge does it should be 5 to 10 psi when turning over as it starts should go up to 20 or 25 at idle bring up the rpm and gauge should go to 30 or 35 but if the needle begins to flutter bouncing really fast then you have a mechanical issue loosing compression or something in that nature if this dont help then take a look at the exhaust see is it blowing black smoke if its doing that too much gas at the cylenders good luck

 

Sounds like valve springs. What cam, lifters, springs, push rods, and heads are you running?