No acceleration at all.

[g4ebguy90]

Alright guys, just dropped in a 6 bolt. FInally got the idle a little under control by adjusting the cable.

Anyways, The car will simply not go. I can get up to around 2 or 3k. but no power at all. It builds boost. But it's like it simply will not go. I'm kinda confused... It idles just fine, doesn't miss or anything. Just as soon as i hit the throttle, she falls on her face, misses a tiny bit, and just will not accelerate.

I could hold the throttle full in 1st and go no were practically.

Any clues.

The car is also very hard to start. Takes a couple tries, but then after that she usually can start right up.

 

[phunny]

Any mods to this engine? Tell us more about the engine you installed

 

[Geier]

Have you done a compression test first?

Now, do a boost leak check. Is your timing correct? I doubt either of these things have been addressed.

If all these are in order, I would say spark plugs and wires. The 3 tests I first talked about are all free with the right tools. Find these tools and perform the diagnosis.

 

[thomcasey]

Alright guys, just dropped in a 6 bolt. FInally got the idle a little under control by adjusting the cable.

Anyways, The car will simply not go. I can get up to around 2 or 3k. but no power at all. It builds boost. But it's like it simply will not go. I'm kinda confused... It idles just fine, doesn't miss or anything. Just as soon as i hit the throttle, she falls on her face, misses a tiny bit, and just will not accelerate.

I could hold the throttle full in 1st and go no were practically.

Any clues.

The car is also very hard to start. Takes a couple tries, but then after that she usually can start right up.

So, you dropped in a turbo motor into your N/T car? Did you change out the ECU/wiring and injectors? What about the fuel pump?

 

[g4ebguy90]

Sorry guys, it's a 6 bolt, in a 1991 GS with a GST engine. It was fine before with a different motor, but that one spun a bearing. I swapped heads and put this one in. Now theres this problem.

I have no idea what way to put the wires, but i highly doubt they are installed wrong, the car does idle very good, and doesnt miss at all. it's just when you hit the throttle. I will check the plugs in a bit, I will buy a compression tester soon, and timing I will have to check after i take, off everything. But i checked before I installed the engine, and it was still good.

 

[Frickadella]

I had a similar experience, idled fine, dogged under load. Turned out to be an arcing plug wire.

 

[captainzib]

I experienced the same symptoms once, and it turned out that one of my intermediate shaft bracket bolts backed out, and the other snapped, so the shaft backed out of the trans.

Check that out. It might not be your issue, but it was mine when the symptoms were exactly the same.

 

[DsmDanny98]

I've had the same issue with a different car turned out the cat got clogged and the insides exploded. That or a boost leak.

What turbo is it running? What injectors and fuel pump? Might be a fuel issue

 

[g4ebguy90]

The plugs are coming back Black... I figured that would mean it's running rich. I put new ones in and they were just a tad bit silver after a run around the block.

14b, 450cc, Fuel pump is unknown. But seems to have the power there. I had a different engine in, and she was alright. But I wouldn't doubt that it could be bad.

 

[DSM_munky_man]

Was the other engine also a turbo engine? cause if not then you need a whole new harness and ocmputer...Also, maybe a rich running problem? if the plugs were black then to me thats what that indicates and is likely a big cause to this problem.

 

[g4ebguy90]

It was a rebuilt turbo block that I used. All I did, was swap some cooling line stuff and the oil filter housing. The head was swapped from my 91 onto the 90. I don't see how the blocks would make and difference sensor wise.

 

[DSM_munky_man]

No, blocks wont, but if you have a NT car and your trying to run a turbo engine on the NT computer and harness you will have issues...

 

[g4ebguy90]

Ok, When I bought this car. It had a 6 bolt turbo engine in it. It ran good, idled good, and boosted very good. No problems. It spun a bearing. I pulled the engine out. I swapped heads with a good engine. i dropped it back in. Now this. The only thing that I believe could have damaged anything would be that the wire I used to lift the engine snapped and went under the CAM sensor. But it seems to be good. I need to test it, I can even swap it. But it seems to work.

Car runs, sometimes it will idle high but not low... It usually goes from 1000 to 1500 and repeats vroom pa vroom pa.

I can rev it high only in neutral or with the clutch in before going in gear , As soon as it sees load * let clutch pedal out* it stops reving misfires, cuts out, and doesn't want to move. I will post a video up probaly tomorrow.

Yesterday a couple times with the MAF unhooked, I could floor it and it would FLY. but thats the only time it ran good. Was at full throttle.

 

[sbeck]

It sounds to me like you have a air leak after your maf or a bad maf. Your BOV is recirced right? I had the same problem on my SR swapped 240 and not one but two BOV's were leaking under load and since I didn't recirc them they were just leaking boost into the atmosphere and drove me crazy trying to diagnose it.

If you haven't done it already dsmlink is the best mod because of the ability to diagnose problems like a factory scan tool can.

 

[g4ebguy90]

What is DSMLINK? I have never ever seriously heard of it, or know how it works or what it does.

My BOV is recirculated.

 

[sbeck]

It is a tuning program and makes your factory ecu tuneable like a stand alone ecu. It allows full control over fuel, timing, and misc. ecu functions. ECMTuning, Inc.

Go to the site and look at the demos its super high quality for the low price of v3 lite $375.00 and there a supporting vendor.

 

[Rideit636]

I've seen collapsed flex-pipes cause similar symptoms. But you seem to have narrowed it down to something MAF related. Good luck.

 

[g4ebguy90]

It is not MAF related though. I acts up hooked up or not.

 

[sbeck]

Running the car with the maf disconnected will make the car run in open loop / limphome mode so it is not a definite MAF. If you get totally stuck I would take it to a pro the headaches saved can be worth every dollar spent. AMS is in Illinois but I am not sure about any pros in Indiana.

 

[g4ebguy90]

, I'll figure it out myself. I mean the old engine ran good. It has to be something I overlooked, or broke during install.

I almost have a 2yr degree in automotive so, there really isn't a point in taking it to a dealer. Getting it towed to a actual DSM tuner, would probaly cost as much as a whole nother 6 bolt engine.

 

[sbeck]

, I'll figure it out myself. I mean the old engine ran good. It has to be something I overlooked, or broke during install.

I almost have a 2yr degree in automotive so, there really isn't a point in taking it to a dealer. Getting it towed to a actual DSM tuner, would probaly cost as much as a whole nother 6 bolt engine.

A dealer wont even look at a swapped car usually.... I am an ASE master GM dealer tech but if I get stuck I still go to someone with more experience than me. You can spend months and lots of money guessing when a pro can take 30 minutes and find what is wrong. Good luck and I definitely recommend dsmlink if you want to master your dsm.

 

[g4ebguy90]

I wouldn't say its swapped. Has a turbo harness, turbo ECU, and turbo engine.
Yes it is a swap, but its a FULL swap. All that i don't know about it, is the fuel pump, which will probaly be checked soon enough .

I wouldn't take pride in myself taking it to someone else. I will just let my instructors look at when school starts, have it towed if I have to. But I'm sure she will be good by then.

 

[darkiller_666]

Black plugs and hard start and not accelerating?? Sounds like ignition! Did you check the ignition system??? PTU coil wires??? Had very similar symptoms when PTU was shorting out, and also when I had a bad coil!

 

[g4ebguy90]

Like I said, before the head with everything still bolted on, Wires, Coil, Transister, was swapped straight up. It was plug and play. I can't believe they would go bad.

My theory which I have to prove tomorrow. Is that the timing is screwed up somehow, or I have a intake leak I am not aware of.

 

[talonDSMerr]

Did you ever get to setting the base timing correctly?