The model produces weird or garbled output
Most likely: chat template mismatch.
Short answer
Most likely: chat template mismatch. Fix in one step: open the model’s Edit dialog and switch the “Chat template” dropdown from Auto-detect to the correct family for your model. Second possibility: quantization too aggressive (Q2/Q3 sometimes fall apart) - download a Q4 or higher variant.
Detailed explanation
Symptoms of chat template mismatch:
- Visible special tokens in the output (
<|im_end|>,<|eot_id|>,<start_of_turn>, etc.) - Model hallucinates additional user/assistant turns
- Output starts fine then devolves into nonsense
- Model refuses to respond or generates a single character
Abliteration auto-detects the chat template on model add. For most modern models this works. When it doesn’t, the fix is direct - set the correct template manually.
Fix - manual template override:
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Go to Models tab
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Click ⋯ on the misbehaving model → Edit
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Find the “Chat template” dropdown (currently on “Auto-detect”)
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Switch to the correct family for your model:
- Llama - for Llama-3, Llama-3.1, Llama-3.2 based models
- Qwen - for Qwen 2.5, Qwen3 based models
- ChatML - safe default for most modern models
- Gemma - for Gemma 2, Gemma 3 based models
- Mistral - for Mistral 7B, Mixtral based models
- Phi - for Phi-3, Phi-3.5 based models
- DeepSeek - for DeepSeek models
- Or one of GLM, Kimi, Command-R, Yi, InternLM, Baichuan, OLMo, Falcon
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Save. The change applies on next model load - close and reopen the chat, or send a new message.
If you don’t know your model’s family, check its Hugging Face page - the README almost always names the chat format. Or try ChatML first, then Llama or Qwen - one of them fits ~80% of modern models.
Symptoms of over-aggressive quantization:
- Model is grammatically fine but semantically nonsensical
- Repetitive phrasing, gets stuck in loops
- Forgets basic facts it should know
- Feels much dumber than the parameter count would suggest
Q2 and Q3 quantizations compress weights so hard that quality can drop off a cliff. Q4 is usually the safe floor.
Fix: download a Q4_K_M or higher variant. If your RAM can’t handle it, pick a smaller model at Q4 instead of the same model at Q2.
Symptoms of just-a-bad-model:
- Consistent low quality across topics with all templates
- Was already reported as low-quality by the community
- Fine-tune of a smaller base than claimed
Some GGUFs floating around Hugging Face are experimental, broken merges, or just bad.
Fix: check the model’s Hugging Face page for comments and downloads count. Well-tested models have thousands of downloads and comment threads. New/obscure ones may just not work.
Why it matters
“Weird output” has three causes with different fixes. Chat template mismatch is the most common and the easiest to fix - one dropdown change. Diagnosing which cause you have determines whether it’s a 10-second fix or a re-download.
In Abliteration specifically
The Chat template dropdown in the Edit dialog is always available. Auto-detect is the default; explicit family values override detection. This is a real fix, not a workaround.
Related
- Chat template auto-detection - how detection works
- Edit model dialog - where the dropdown lives
- Quantization - the second most common cause